Twenty Questions
Encyclopedia
Twenty Questions is a spoken
Spoken game
A spoken game is a game which uses words instead of cards, boards, game pieces, or other paraphernalia.Spoken games can often also be categorized as guessing games, word games, or because of their freedom from equipment or visual engagement, car games....

 parlor game
Parlour game
A parlour game is a group game played indoors. During the Victorian era in Great Britain and in the United States, these games were extremely popular among the upper and middle classes. They were often played in a parlour, hence the name....

 which encourages deductive reasoning
Deductive reasoning
Deductive reasoning, also called deductive logic, is reasoning which constructs or evaluates deductive arguments. Deductive arguments are attempts to show that a conclusion necessarily follows from a set of premises or hypothesis...

 and creativity
Creativity
Creativity refers to the phenomenon whereby a person creates something new that has some kind of value. What counts as "new" may be in reference to the individual creator, or to the society or domain within which the novelty occurs...

. It originated in the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...

 and escalated in popularity during the late 1940s when it became the format for a successful weekly radio quiz program.

In the traditional game, one player is chosen to be the answerer. That person chooses a subject but does not reveal this to the others. All other players are questioners. They each take turns asking a question which can be answered with a simple "Yes" or "No." In variants of the game (see below), multiple state answers may be included such as the answer "Maybe." The answerer answers each question in turn. Sample questions could be: "Is it bigger than a breadbox?
What's My Line?
What's My Line? is a panel game show which originally ran in the United States on the CBS Television Network from 1950 to 1967, with several international versions and subsequent U.S. revivals. The game tasked celebrity panelists with questioning contestants in order to determine their occupations....

" or "Can I put it in my mouth?" Lying is not allowed, as it would ruin the game. If a questioner guesses the correct answer, that questioner wins and becomes the answerer for the next round. If 20 questions are asked without a correct guess, then the answerer has stumped the questioners and gets to be the answerer for another round.

Careful selection of questions can greatly improve the odds of the questioner winning the game. For example, a question such as "Does it involve technology for communications, entertainment or work?" can allow the questioner to cover a broad range of areas using a single question that can be answered with a simple "yes" or "no". If the answerer responds with "yes," the questioner can use the next question to narrow down the answer; if the answerer responds with "no," the questioner has successfully eliminated a number of possibilities for the answer.

The game of 20 Questions is fun, but it is also instructive for both children and adults in that it requires understanding of logic, objective facts and language.

Popular variants

The most popular variant is called "Animal, Vegetable, Mineral." This is taken from the Linnaean taxonomy
Linnaean taxonomy
Linnaean taxonomy can mean either of two related concepts:# the particular form of biological classification set up by Carl Linnaeus, as set forth in his Systema Naturæ and subsequent works...

 of the natural world. In this version, the answerer tells the questioners at the start of the game whether the subject belongs to the animal
Animal
Animals are a major group of multicellular, eukaryotic organisms of the kingdom Animalia or Metazoa. Their body plan eventually becomes fixed as they develop, although some undergo a process of metamorphosis later on in their life. Most animals are motile, meaning they can move spontaneously and...

, vegetable
Vegetable
The noun vegetable usually means an edible plant or part of a plant other than a sweet fruit or seed. This typically means the leaf, stem, or root of a plant....

 or mineral
Mineral
A mineral is a naturally occurring solid chemical substance formed through biogeochemical processes, having characteristic chemical composition, highly ordered atomic structure, and specific physical properties. By comparison, a rock is an aggregate of minerals and/or mineraloids and does not...

 kingdom. These categories can produce odd technicalities, such as a wooden table being classified as a vegetable (since wood comes from trees), or a belt being both animal and mineral (because its leather comes from the hide of an animal unless it is synthetic, and its buckle is made of metal).

This version is referred to in the "Major-General's Song
Major-General's Song
I Am the Very Model of a Modern Major-General is a patter song from Gilbert and Sullivan's 1879 comic opera The Pirates of Penzance. It is perhaps the most famous song in Gilbert and Sullivan's operas. It is sung by Major-General Stanley at his first entrance, towards the end of Act I...

," a piece from the Gilbert and Sullivan
Gilbert and Sullivan
Gilbert and Sullivan refers to the Victorian-era theatrical partnership of the librettist W. S. Gilbert and the composer Arthur Sullivan . The two men collaborated on fourteen comic operas between 1871 and 1896, of which H.M.S...

 opera The Pirates of Penzance
The Pirates of Penzance
The Pirates of Penzance; or, The Slave of Duty is a comic opera in two acts, with music by Arthur Sullivan and libretto by W. S. Gilbert. The opera's official premiere was at the Fifth Avenue Theatre in New York City on 31 December 1879, where the show was well received by both audiences...

:
"I am the very model of a modern Major-General. I've information vegetable, animal, and mineral, I know the kings of England, and I quote the fights historical."


Other versions specify that the item to be guessed should be in a given category, such as actions, occupation
Profession
A profession is a vocation founded upon specialized educational training, the purpose of which is to supply disinterested counsel and service to others, for a direct and definite compensation, wholly apart from expectation of other business gain....

s, famous people
Celebrity
A celebrity, also referred to as a celeb in popular culture, is a person who has a prominent profile and commands a great degree of public fascination and influence in day-to-day media...

, etc. In Hungary
Hungary
Hungary , officially the Republic of Hungary , is a landlocked country in Central Europe. It is situated in the Carpathian Basin and is bordered by Slovakia to the north, Ukraine and Romania to the east, Serbia and Croatia to the south, Slovenia to the southwest and Austria to the west. The...

, a similar game is named after Simon bar Kokhba. A version of Twenty Questions called Yes and No
Yes and No
Yes and No is a spoken word game similar to Twenty Questions played in Charles Dickens' A Christmas Carol. In the game, the host has something in mind, and the guessers ask several simple yes-or-no questions...

 is played as a parlor game by characters of Charles Dickens
Charles Dickens
Charles John Huffam Dickens was an English novelist, generally considered the greatest of the Victorian period. Dickens enjoyed a wider popularity and fame than had any previous author during his lifetime, and he remains popular, having been responsible for some of English literature's most iconic...

' A Christmas Carol
A Christmas Carol
A Christmas Carol is a novella by English author Charles Dickens first published by Chapman & Hall on 17 December 1843. The story tells of sour and stingy Ebenezer Scrooge's ideological, ethical, and emotional transformation after the supernatural visits of Jacob Marley and the Ghosts of...

. A children's version is played with the categories, "Animal, Vegetable, Mineral, Candy."

In another version, the answerer claims to have a story in mind and the questioners are to attempt to obtain and retell the story via twenty questions. But, without the questioners' knowing, the answerer actually has no story in mind, and answers the questions "yes" or "no" according to some set rule, such as whether the question ends in a vowel or consonant (and "maybe" if the question ends in "y"). After the twenty questions the questioners try to retell the story according to the answers, which results in laughs for everyone.

Computers, scientific method, and situation puzzles

The game suggests that the information (as measured by Shannon's entropy
Information entropy
In information theory, entropy is a measure of the uncertainty associated with a random variable. In this context, the term usually refers to the Shannon entropy, which quantifies the expected value of the information contained in a message, usually in units such as bits...

 statistic) required to identify an arbitrary object is at most 20 bit
Bit
A bit is the basic unit of information in computing and telecommunications; it is the amount of information stored by a digital device or other physical system that exists in one of two possible distinct states...

s. The game is often used as an example when teaching people about information theory
Information theory
Information theory is a branch of applied mathematics and electrical engineering involving the quantification of information. Information theory was developed by Claude E. Shannon to find fundamental limits on signal processing operations such as compressing data and on reliably storing and...

. Mathematically, if each question is structured to eliminate half the objects, 20 questions will allow the questioner to distinguish between 220 or 1,048,576 subjects. Accordingly, the most effective strategy for Twenty Questions is to ask questions that will split the field of remaining possibilities roughly in half each time. The process is analogous to a binary search algorithm
Binary search algorithm
In computer science, a binary search or half-interval search algorithm finds the position of a specified value within a sorted array. At each stage, the algorithm compares the input key value with the key value of the middle element of the array. If the keys match, then a matching element has been...

 in computer science
Computer science
Computer science or computing science is the study of the theoretical foundations of information and computation and of practical techniques for their implementation and application in computer systems...

 or successive approximation ADC
Successive approximation ADC
A successive approximation ADC is a type of analog-to-digital converter that converts a continuous analog waveform into a discrete digital representation via a binary search through all possible quantization levels before finally converging upon a digital output for each conversion.-Block...

 in analog-to-digital signal conversion.

In 1901 Charles Sanders Peirce discussed factors in the economy of research that govern the selection of a hypothesis for trial — (1) cheapness, (2) intrinsic value (instinctive naturalness and reasoned likelihood), and (3) relation (caution, breadth, and incomplexity) to other projects (other hypotheses and inquiries). He discussed the potential of Twenty Questions to single one subject out from among 220 and, pointing to skillful caution, said,
He elaborated on how, if that principle had been followed in the investigation of light, its investigators would have saved themselves from half a century of work. Note that testing the smallest logical components of a hypothesis one at a time does not mean asking about, say, 1,048,576 subjects one at a time. Instead it means extracting aspects of a guess or hypothesis, and asking, for example, "did an animal do this?" before asking "did a horse do this?".

That aspect of scientific method
Scientific method
Scientific method refers to a body of techniques for investigating phenomena, acquiring new knowledge, or correcting and integrating previous knowledge. To be termed scientific, a method of inquiry must be based on gathering empirical and measurable evidence subject to specific principles of...

 resembles also a situation puzzle
Situation puzzle
Situation puzzles are often referred to as lateral thinking puzzles or "yes/no" puzzles.Situation puzzles are usually played in a group, with one person hosting the puzzle and the others asking questions which can only be answered with a "yes" or "no" answer...

 in facing (unlike Twenty Questions) a puzzling scenario at the start. Both games involve asking yes/no questions, but Twenty Questions places a greater premium on efficiency of questioning. A limit on their likeness to the scientific process of trying hypotheses is that a hypothesis, because of its scope, can be harder to test for truth (test for a "yes") than to test for falsity (test for a "no") or vice versa (see Falsifiability
Falsifiability
Falsifiability or refutability of an assertion, hypothesis or theory is the logical possibility that it can be contradicted by an observation or the outcome of a physical experiment...

).

Radio

In the 1940s the game became a popular radio panel quiz show, Twenty Questions, first broadcast at 8pm, Saturday, February 2, 1946, on the Mutual Broadcasting System
Mutual Broadcasting System
The Mutual Broadcasting System was an American radio network, in operation from 1934 to 1999. In the golden age of U.S. radio drama, MBS was best known as the original network home of The Lone Ranger and The Adventures of Superman and as the long-time radio residence of The Shadow...

 from New York's Longacre Theatre
Longacre Theatre
The Longacre Theatre is a Broadway theatre located at 220 West 48th Street in midtown Manhattan.-Theatre History:Designed by architect Henry Beaumont Herts in 1912, it was named for Longacre Square, the original name for Times Square...

 on West 48th Street. Radio listeners sent in subjects for the panelists to guess in 20 questions; Winston Churchill
Winston Churchill
Sir Winston Leonard Spencer-Churchill, was a predominantly Conservative British politician and statesman known for his leadership of the United Kingdom during the Second World War. He is widely regarded as one of the greatest wartime leaders of the century and served as Prime Minister twice...

's cigar was the subject most frequently submitted. On the early shows, listeners who stumped the panel won a lifetime subscription to Pageant
Pageant (magazine)
Pageant was a 20th-century monthly magazine published in the United States from November 1944 until February 1977. Printed in a digest size format, it became Coronet magazine's leading competition, although it aimed for comparison to Reader's Digest....

. From 1946 to 1951, the program was sponsored by Ronson Lighters. In 1952-53, Wildroot Cream-Oil was the sponsor.

The show was the creation of Fred Van Deventer, who was born December 5, 1903 in Tipton, Indiana, and died December 2, 1971. Van Deventer was a WOR Radio newscaster with New York's highest-rated news show, Van Deventer and the News. Van Deventer was on the program's panel with his wife, Florence Van Deventer, who used her maiden name, appearing on the show as Florence Rinard. Their 14-year-old son, Robert Van Deventer (known on the show as Bobby McGuire) and the program's producer, Herb Polesie, completed the regular panel with daughter Nancy Van Deventer joining the group on occasions. Celebrity guests sometimes contribute to identifying the subject at hand.

The Van Deventer family had played the game for years at their home, long before they brought the game to radio, and they were so expert at it that they could often nail the answer after only six or seven questions. On one memorable show, Maguire succeeded in giving the correct answer (Brooklyn) without asking a single question. The studio audience was shown the answer in advance and Maguire based his answer on the audience's reaction; during the 1940s, New York radio studio audiences included many Brooklynites, and they cheered wildly whenever Brooklyn
Brooklyn
Brooklyn is the most populous of New York City's five boroughs, with nearly 2.6 million residents, and the second-largest in area. Since 1896, Brooklyn has had the same boundaries as Kings County, which is now the most populous county in New York State and the second-most densely populated...

 was mentioned in any context.

The moderator was sportscaster Bill Slater
Bill Slater (broadcaster)
Bill Slater was an educator, sports announcer, and radio/television personality from the 1920s through the 1950s. He was perhaps best known for hosting the radio shows Twenty Questions and Luncheon at Sardi's...

 who opened each session by giving the clue as animal, vegetable, or mineral. He then answered each query from panel members. This cast remained largely intact throughout the decade-long run of the show. Slater was succeeded at the beginning of 1953 by Jay Jackson
Jay Jackson
Jay Jackson was an American radio and television quiz show host and announcer more familiar for a one-off, fictitious host he played on a legendary situation comedy than he was during his time as a real radio and television performer.Jackson was the master of ceremonies of the panel quiz show...

, who remained through the final broadcast, and there were two changes in the panel's juvenile chair. When McGuire graduated from high school, his decision to attend the North Carolina-based Duke University
Duke University
Duke University is a private research university located in Durham, North Carolina, United States. Founded by Methodists and Quakers in the present day town of Trinity in 1838, the school moved to Durham in 1892. In 1924, tobacco industrialist James B...

 meant he could no longer remain on the program, so he asked his high school friend Johnny McPhee
John McPhee
John Angus McPhee is an American Pulitzer Prize-winning writer, widely considered one of the pioneers of creative nonfiction....

 to replace him. Since McPhee was attending nearby Princeton University
Princeton University
Princeton University is a private research university located in Princeton, New Jersey, United States. The school is one of the eight universities of the Ivy League, and is one of the nine Colonial Colleges founded before the American Revolution....

, he was thus geographically available for the production in New York. McPhee continued until he graduated and was himself succeeded by Dick Harrison (real name John Beebe) in September 1953. Harrison continued until early 1954, when he was replaced by Bobby McGuire, then 22 years old. McGuire appeared as the "oldest living teenager" until the end of the run.

Television

As a television series, Twenty Questions debuted as a local show in New York on WOR-TV
WWOR-TV
WWOR-TV, virtual channel 9 , is the flagship station of the MyNetworkTV programming service, licensed to Secaucus, New Jersey and serving the Tri-State metropolitan area. WWOR is owned by Fox Television Stations, a division of the News Corporation, and is a sister station to Fox network flagship...

 Channel 9 on November 2, 1949. Beginning on November 26, the series went nationwide on NBC
NBC
The National Broadcasting Company is an American commercial broadcasting television network and former radio network headquartered in the GE Building in New York City's Rockefeller Center with additional major offices near Los Angeles and in Chicago...

 until December 24, after which it remained dormant until March 17, 1950 when it was picked up by ABC
American Broadcasting Company
The American Broadcasting Company is an American commercial broadcasting television network. Created in 1943 from the former NBC Blue radio network, ABC is owned by The Walt Disney Company and is part of Disney-ABC Television Group. Its first broadcast on television was in 1948...

 until June 29, 1951.

Its longest and most well-known run, however, is the one on the DuMont Television Network
DuMont Television Network
The DuMont Television Network, also known as the DuMont Network, DuMont, Du Mont, or Dumont was one of the world's pioneer commercial television networks, rivalling NBC for the distinction of being first overall. It began operation in the United States in 1946. It was owned by DuMont...

 from July 6, 1951 to May 30, 1954; during this time, original host Bill Slater
Bill Slater (broadcaster)
Bill Slater was an educator, sports announcer, and radio/television personality from the 1920s through the 1950s. He was perhaps best known for hosting the radio shows Twenty Questions and Luncheon at Sardi's...

 was replaced by Jay Jackson. After this run ended, ABC picked up the series once again from July 6, 1954 to May 3, 1955. The last radio show had been broadcast on March 27, 1954.

See also List of programs broadcast by the DuMont Television Network and List of surviving DuMont Television Network broadcasts.

In 1975, a pilot for a revival was made with host Jack Clark
Jack Clark (television)
Jack Clark was an American television game show host and announcer. He is best known for hosting The Cross-Wits, and as an offstage announcer for Wheel of Fortune...

, which did not sell.


Episode status

Like many game shows of the era, Twenty Questions was a victim of wiping
Wiping
Wiping or junking is a colloquial term for action taken by radio and television production and broadcasting companies, in which old audiotapes, videotapes, and telerecordings , are erased, reused, or destroyed after several uses...

. A DuMont episode from January 18, 1952 and the 1975 pilot circulate among collectors. It is unknown how many radio episodes survive.

United Kingdom

The BBC
BBC
The British Broadcasting Corporation is a British public service broadcaster. Its headquarters is at Broadcasting House in the City of Westminster, London. It is the largest broadcaster in the world, with about 23,000 staff...

 aired a version on radio from February 28, 1947 to 1976 with TV specials airing in 1947 and 1948 plus a series from 1956-1957. On radio, the subject to be guessed was revealed to the audience by a "mystery voice" (originally Norman Hackforth
Norman Hackforth
Norman Hackforth, Sir Noël Coward's renowned English accompanist and a gifted musician was born in Gaya, Bihar India on 20 December 1908.Hackforth's relationship with Noël Coward began in 1941, when he succeeded Elsie April and Robb Stewart as his arranger...

 from 1947-1962; he was later a regular panelist). Hackforth became well-known amongst the British public as much for his aloofness as his apparent knowledgeability.

The series was originally presented by Gilbert Harding
Gilbert Harding
Gilbert Charles Harding was a British journalist and radio and television personality. His many careers included schoolmaster, journalist, policeman, disc-jockey, interviewer and television presenter...

, who was ousted in 1960 by producer Ian Messiter
Ian Messiter
Ian Cassan Messiter was a BBC Radio producer and the creator of a number of panel games, including Just a Minute, and Many a Slip. He was also the Programme Associate on Family Fortunes. Messiter was born in Dudley, Worcestershire and educated at Sherborne School in Dorset...

 when, after having drunk a triple gin-and-tonic he had originally offered to Messiter, he proceeded to completely ruin the night's game – he insulted two panelists, failed to recognise a correct identification after seven questions (after revealing the answer upon the 20th question, he yelled at the panel and audience), and ended the show three minutes early by saying "I'm fed up with this idiotic game ... I'm going home"). He was replaced by Kenneth Horne
Kenneth Horne
Kenneth Horne was an English comedian and businessman. The son of a clergyman and politician, he combined a successful business career with regular broadcasting for the BBC. His first hit series Much-Binding-in-the-Marsh written with his co-star Richard Murdoch arose out of his wartime service as...

 until 1967, followed by David Franklin
David Franklin (broadcaster)
David Franklin was a British opera singer and broadcaster.Born in London in 1908, David Franklin originally trained as a schoolteacher. A bass singing in amateur productions, he was discovered in 1934 by John Christie, the founder of the Glyndebourne festival...

 from 1970-1972.

A revival ran for one season in the 1990s on BBC Radio 4
BBC Radio 4
BBC Radio 4 is a British domestic radio station, operated and owned by the BBC, that broadcasts a wide variety of spoken-word programmes, including news, drama, comedy, science and history. It replaced the BBC Home Service in 1967. The station controller is currently Gwyneth Williams, and the...

, hosted by Jeremy Beadle
Jeremy Beadle
Jeremy James Anthony Gibson-Beadle MBE was an English television presenter, writer and producer. During the 1980s, he was a regular face on British television and in two years appeared 50 weeks of the year. His shows regularly topped the charts beating Coronation Street and EastEnders on one...

. A version with a rival line-up, produced by commercial station Radio Luxembourg
Radio Luxembourg (English)
Radio Luxembourg is a commercial broadcaster in many languages from the Grand Duchy of Luxembourg. It is nowadays known in most non-English languages as RTL ....

, is not acknowledged by the BBC.

A televised version ran from 1960-1961, produced by Associated-Rediffusion
Associated-Rediffusion
Associated-Rediffusion, later Rediffusion, London, was the British ITV contractor for London and parts of the surrounding counties, on weekdays between 1954 and 29 July 1968. Transmissions started on 22 September 1955.-Formation:...

 for ITV
ITV
ITV is the major commercial public service TV network in the United Kingdom. Launched in 1955 under the auspices of the Independent Television Authority to provide competition to the BBC, it is also the oldest commercial network in the UK...

 and hosted by Peter Jones
Peter Jones
Peter Jones or Pete Jones may refer to:*Peter Jones , English actor*Peter Jones , Australian rules footballer for Carlton...

 (who later hosted in 1974). The "mystery voice" later became a running gag on the radio series I'm Sorry I Haven't A Clue
I'm Sorry I Haven't a Clue
I'm Sorry I Haven't a Clue, sometimes abbreviated to ISIHAC or Clue, is a BBC radio comedy panel game broadcast since 11 April 1972 at the rate of one or two series each year , transmitted on BBC Radio 4, with occasional repeats on BBC Radio 4 Extra and the BBC's World Service...

.

Canada

Twenty Questions
Twenty Questions (Canadian TV series)
Twenty Questions was a Canadian television game show, which aired on CTV in the 1961-62 television season. Produced by CJAY-TV in Winnipeg and hosted by Stewart Macpherson, the show was an adaptation of the earlier American game show Twenty Questions....

aired on CTV
CTV television network
CTV Television Network is a Canadian English language television network and is owned by Bell Media. It is Canada's largest privately-owned network, and has consistently placed as Canada's top-rated network in total viewers and in key demographics since 2002, after several years trailing the rival...

 in 1961; its host, Stewart Macpherson, went on to become the original host of the UK version.

Norway

NRK aired its own version continuously from 1947 to the early 1980s. In 2004, the radio series was revived and regained its popularity, leading to a 2006 TV version. The Norwegian 20 spørsmål continues on NRK radio and TV, and a web-based game is available at the official NRK website. A 2006 board game based on the series is currently the prize sent to listeners who beat the panel.

Hungary

In Hungary, this game is popularly known as "barkochba", named after Simon bar Kokhba
Simon bar Kokhba
Simon bar Kokhba was the Jewish leader of what is known as the Bar Kokhba revolt against the Roman Empire in 132 CE, establishing an independent Jewish state of Israel which he ruled for three years as Nasi...

, the leader of the second century Jewish uprising against the Romans. The story goes that the Romans cut out his spy's tongue, so when he reached bar Kokhba's camp, he was able to nod or shake his head only to answer bar Kokhba's questions. The game is not usually played in the media, but at parties, and it is widely known since at least 1922, first invented sometime after 1900, see http://hu.wikipedia.org/wiki/Barkochba. The number of questions is not limited to twenty.

See also

  • Tactics of 20 Questions Rules and Tactics
  • 20 Questions Play the game online
  • 20Q
    20Q
    20Q is a computerized game of twenty questions that began as an experiment in artificial intelligence . It was invented by Robin Burgener....

     artificial intelligence
  • Guess Who?
    Guess Who?
    Guess Who? is a two-player guessing game created by Ora and Theo Coster, also known as Theora Design, first manufactured by Milton Bradley in 1979 in Great Britain. It was brought to the United States in 1982.-Game play:...

     board game
  • List of programs broadcast by the DuMont Television Network
  • List of surviving DuMont Television Network broadcasts
  • Situation puzzle
    Situation puzzle
    Situation puzzles are often referred to as lateral thinking puzzles or "yes/no" puzzles.Situation puzzles are usually played in a group, with one person hosting the puzzle and the others asking questions which can only be answered with a "yes" or "no" answer...

  • Akinator, the Web Genius
    Akinator
    Akinator, the Web Genius is an internet game based on Twenty Questions that can determine which character the player is thinking by asking him or her a series of questions. It is an Artificial Intelligence program that can find and learn the best questions to be asked to the player. Created by...

    , an on-line version which uses artificial intelligence
    Artificial intelligence
    Artificial intelligence is the intelligence of machines and the branch of computer science that aims to create it. AI textbooks define the field as "the study and design of intelligent agents" where an intelligent agent is a system that perceives its environment and takes actions that maximize its...

    .

External links

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