题解

#include <iostream>
using namespace std;
int a[110];
int main() {
    int n, x, ans = -1;
    cin >> n;
    for (int i = 1; i <= n; i++){
        cin >> a[i];
    }
    cin >> x;
    int l = 1, r = n;
    while (l <= r) {
        int mid = (l + r) >> 1;
        if (a[mid] >= x) {
            r = mid - 1;
            ans = mid;
        }else {
            l = mid + 1;
        }
    }
    cout << ans;
    return 0;
}

#include<bits/stdc++.h>
using namespace std;
int a[110];
int main(){
    int n,m;
    cin>>n;
    for(int i=1;i<=n;i++){
        cin>>a[i];
    }
    cin>>m;
    cout<<lower_bound(a+1,a+n+1,m)-a<<endl;
	return 0;    
}