奇了怪了？感觉没错啊？

#include <cstdio>
using namespace std;
int n, q;
int a[1000005];
int find(int x)
{
    int l = 1, r = n;
    while (l < r)
    {
        int mid = (l+r)/ 2;
        if (a[mid] >= x)
        {
            r = mid;
        }
        else
        {
            l = mid + 1;
        }
    }
    if (a[l] == x)
        return l;
    else
        return -1;
}
int main()
{
    int n, q;
    scanf("%d %d ", &n, &q);
    for (int i = 1; i <= n; i++)
    {
        scanf("%d", &a[i]);
    }
    while (q--)
    {
        int m;
        scanf("%d", &m);
        int ans = find(m);
        printf("%d ", ans);
    }