[C++知识库]聪明人的游戏提高篇：第二章综合练习：decode

#include <iostream>
#include <cstring>
#include <cstdio>
#include <string>
using namespace std;
bool zm[30],wz[30];
string k,m,l="                              ";
int n,i,j,t,len;
int main ()
{
	freopen ("decode.in","r",stdin);
	freopen ("decode.out","w",stdout);
	cin >>m >>n >>k;
	len=m.size()+n;
	for (i=n-1;i<len-1;i++)
	{
		l[i%26]=m[i-n+1];
		zm[int(m[i-n+1])-65]=0;
		wz[i%26]=0;
	}
	for (j=i,i=0;i<26;j++)
	{
		if (j>26)
			j=1;
		if (wz[j])
		{
			while (!zm[i])
				i++;
			if (i<26)
				l[j]=i+65;
			i++;
		}
	}
	len=k.size();
	for (i=0;i<len;i++)
		cout <<char(l.find(k[i])%26+65);
	return 0;
}