题解 | #查找#

#include<cstdio>
#include<algorithm>

using namespace std;
int arr[100];//使用全局数组

bool binarySearch(int n, int x) {
    int left = 0;
    int right = n - 1;
    while (left <= right) {
        int mid = (left + right) / 2;
        if (arr[mid] == x) {
            return true;
        } else if (arr[mid] > x) {
            right = mid - 1 ;
        } else {
            left = mid + 1 ;
        }
    }
    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 x;
            scanf("%d", &x);
            if (binarySearch(n, x) == true) {
                printf("YES\n");
            } else {
                printf("NO\n");
            }
        }
    }
}