Luogu 1071 - 潜伏者 - [字符串]

#include<bits/stdc++.h>
using namespace std;
int f[30],cnt[30];
string x,y,s;
int main()
{
    cin>>x>>y>>s;

    if(x.size()!=y.size())
    {
        cout<<"Failed"<<endl;
        return 0;
    }

    memset(f,0,sizeof(f));
    for(int i=0;i<x.size();i++)
    {
        if(!f[x[i]-‘A‘+1]) f[x[i]-‘A‘+1]=y[i]-‘A‘+1;
        else if(f[x[i]-‘A‘+1]!=y[i]-‘A‘+1)
        {
            cout<<"Failed"<<endl;
            return 0;
        }
    }

    for(int i=1;i<=26;i++)
    {
        if(!f[i])
        {
            cout<<"Failed"<<endl;
            return 0;
        }
        else
        {
            cnt[f[i]]++;
            if(cnt[f[i]]>1)
            {
                cout<<"Failed"<<endl;
                return 0;
            }
        }
    }

    for(int i=0;i<s.size();i++) s[i]=‘A‘+f[s[i]-‘A‘+1]-1;
    cout<<s<<endl;
}