The question is similar to this question from Codechef : Contest Page

Apparently my code has been accepted for all the tasks except for the 5th. Can someone please tell me why

using namespace std;

int main(){

long long int n,h,x;

long long int i=0;

cin>>n>>h;

long long int arr[n];

for(int i=0; i<n; i++){

cin>>arr[i];

}