还是喜欢FOR循环

#include<bits/stdc++.h>
using namespace std;
long long n,a[99999],m,x = -1;
int main(){
cin >> n;
for(int i = 1;i <= n;i++){
cin >> a[i];
}
cin >> m;
for(int i = 1;i <= n;i++){
if(a[i] >= m){
if(x == -1){
x = i;
}
}
}
cout << x;
return 0;
}