题解 | #查找学生信息#

#include <iostream>
#include <map>

using namespace std;

struct student{
    string name;
    string sex;
    int age;
    student():name("无名氏"),sex("男"),age(0){} // 需要一个空参数的构造器，因为[]操作符没找到键时会初始化一个空值，需要调用空参构造
    student(string str,string c,int a):name(str),sex(c),age(a){}
};

int main(){
    int n,m;
    while (cin>>n) {
        map<string,student> stuMap;
        string key,str,c;
        int a;
        for (int i = 0; i < n; ++i) {
            cin>>key>>str>>c>>a;
            stuMap.insert(pair<string,student>(key,student(str,c,a))); // 不能用=号赋值，将struct通过=赋值需要重载=号
        }

        cin>>m;
        for (int i = 0; i < m; ++i) {
            cin>>key;
            if (stuMap.find(key)!=stuMap.end()){
                cout<<key<<" "<<stuMap[key].name<<" "<<stuMap[key].sex<<" "<<stuMap[key].age<<endl;
            } else{
                cout<<"No Answer!"<<endl;
            }
        }
    }

    return 0;
}