一种playfair密码变种加密方法如下:首先选择一个密钥单词(称为pair...答:include<stdio.h> include<string.h> int find(char *key,int n,char c);char alph[26]={'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'};void find_fang(char fang[5][5],...