#include <iostream>
using namespace std;
int main(){
  int n;int h=0;
  cin >> n;
  int arr[n];
  for(int i=0;i<n;++i){
    cin >> a[i];
  }
  for(int i=1;i<=n;++i){
    if(a[i-1]>a[i]{
      h=h+(a[i-1]-a[i]);
      a[i]=a[i]+(a[i-1]-a[i]);
  }
  return 0;
}