#include <stdio.h> int main() { char a;//准备输入的字符变量 char arr[53]={'a','b','c','d','e','g','h','i','j','k','l','m','n','o','p','q','r','s','t','u','v','w','x','y','z','A','B','C','D','E','F','G','H','I','J','K','L','M','N','O','P','Q','R','S','T','U','V','W','X','Y','Z'};//用来对比的数组内容 scanf("...