单射函数问题

设函数f将点集S = {0,1, , n -1}映射为f (S) = { f (i) | iÎ S} Í S 。单射函数问题要

从S中选取最大子集X Í S 使f (X )是单射函数。

例如，当n=7， f (S) = {1,0,0,2,2,3,6} Í S 时， X = {0,1,6} Í S 是所求的最大子集。-Injective function, the function f the problem will be the point set based S = (0,1,  , n-1) maps to f (S) = (f (i) | iÎ　S) Í　S. Injective function of the problem from the largest subset of S, select the X Í　S so that f (X) is injective function. For example, when n = 7, f (S) = (1,0,0,2,2,3,6) Í　S, when, X = (0,1,6) Í　S is a subset of the desired maximum.