题解 | #查找#

#include<iostream>
#include<cstdio>
#include<algorithm>

using namespace std;

int arr[1000];

bool bindary(int n, int x) {
    int left = 0;
    int right = n - 1;
    while (left <= right) {
        int middle = left + (right - left) / 2;
        if (arr[middle] < x)
            left = middle + 1;
        else if (arr[middle] > x)
            right = middle - 1;
        else return true;
    }
    return false;
}

int main() {
    int n, m;
    while (scanf("%d", &n) != EOF) {
        for (int i = 0; i < n; i++) {
            scanf("%d", &arr[i]);
        }
        sort(arr, arr + n);
        scanf("%d", &m);
        for (int i = 0; i < m; i++) {
            int t;
            scanf("%d", &t);
            if (bindary(n, t))
                printf("YES\n");
            else printf("NO\n");
        }
    }
    return 0;
}