题解 | #查找#

#include <iostream>
#include <algorithm>
#include <map>
using namespace std;

int main(){
    map<int,int> findIndex;
    int m,n;
    int arr[110];
    while(scanf("%d",&n) !=EOF){
        for(int i=0;i<n;++i){
            scanf("%d",&arr[i]);
            findIndex[arr[i]] = i; //把数组元素作为键,元素下标作为值.

        }

        scanf("%d",&m);
        for(int i=0;i<m;++i){
            int num;
            scanf("%d",&num);
            if(findIndex.find(num) == findIndex.end()){
                printf("NO\n");
            }
            else{
                printf("YES\n");
            }
        }
    }
}