为哈要用结构体

#include<bits/stdc++.h>
using namespace std;
int main(){
    string email; getline(cin,email);
    int n; cin >> n;
    bool flag = false;
    while(n--){
        string a,b,c; cin >> a >> b >> c;
        if(c != email) continue;
        else{
            flag = true;
            int l = b.size();
            for(int i = 0;i < l;i++){
                if(b[i] >= 'a' && b[i] <= 'z') b[i] -= 32;
                else if(b[i] >= 'A' && b[i] <= 'Z') b[i] += 32;
                else continue;
            }
            cout << a << " " << b << endl;
        }
    }
    if(!flag) cout << "empty";
    return 0;
}