#include <stdio.h> #include <string.h> char change(char str) { char number[10] = {'0', '8', '4', 'C','2','A','6','E','1','9'}; char Aa[6] = {'5','D','3','B', '7', 'F'}; if(str >= '0' && str <= '9') { return number[str-'0']; } else if(str >= 'A' && str <= 'F') ...