15. The character input program according to claim 11 , which causes a computer to execute displaying processing of displaying a group of the respective input candidate characters in a different region for each kind of input candidate characters.
11. A character input program for causing a computer integrally or separately provided with an input unit including an n (n is an integer satisfying n=>2) number of selection units to execute: grouping processing of assigning an m-digit n-ary number satisfying X<=nm when the number of input candidate characters which are characters or symbols as an input candidate 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, displaying processing of displaying, on a basis of each of the m digit, the n groups of the respective input candidate characters classified, and character specifying processing of 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.