#include<stdio.h> int main(){ int n,i=0; char a,b,c,d; scanf("%d %c %c %c %c",&n,&a,&b,&c,&d); char s[100]={'0'}; for(i=0;i<=n;i++){ scanf(" %c",&s[i]);//%c前面有个空格用于吸收回车 if(s[i]==a){ s[i]=b; }else if(s[i]==c){ ...