1. A character input system, including: an input unit including an n number (n is an integer satisfying n=>2) of selection units for selecting any group among groups of input candidate characters which are characters or symbols as an input candidate, a grouping unit for assigning an m-digit n-ary number satisfying X<=n m when the number of input candidate characters is set to be X (X is an integer satisfying X=>2) to each input candidate character one-for-one to classify the respective input candidate characters into n groups on a basis of each of m (m is an integer satisfying m=>2) digits, a display unit for displaying, on a basis of each of m digits, the n groups of the respective input candidate characters classified, and a character specifying unit for specifying a value which each digit of an n-ary number can assume and which corresponds to the selection unit operated by a user and specifying one input candidate character according to an m-digit n-ary number determined by m times of operation of the selection unit.
1. A character input system, including: an input unit including an n number (n is an integer satisfying n=>2) of selection units for selecting any group among groups of input candidate characters which are characters or symbols as an input candidate, a grouping unit for assigning an m-digit n-ary number satisfying X<=n m when the number of input candidate characters is set to be X (X is an integer satisfying X=>2) to each input candidate character one-for-one to classify the respective input candidate characters into n groups on a basis of each of m (m is an integer satisfying m=>2) digits, a display unit for displaying, on a basis of each of m digits, the n groups of the respective input candidate characters classified, and a character specifying unit for specifying a value which each digit of an n-ary number can assume and which corresponds to the selection unit operated by a user and specifying one input candidate character according to an m-digit n-ary number determined by m times of operation of the selection unit. 3. The character input system according to claim 1 , wherein said grouping unit determines a part or all of values of digits of an m-digit n-ary number by using a random number.