#include <bits/stdc++.h>
using namespace std;
#define f first
#define s second
#define ll long long
ll N;
ll diffs[100005];
ll res;
int main() {
ios_base::sync_with_stdio(false);
cin.tie(0);
cout.tie(0);
// get difference array
cin >> N;
ll prev, t;
prev = 0;
for (ll i=0; i<N; i++) {
cin >> t;
diffs[i] = t-prev;
prev = t;
}
diffs[N] = 0-prev;
// greedy
res = 0;
stack<ll> holds;
for (ll i=0; i<=N; i++) {
// loop through difference array
if (diffs[i] == 0) continue; // nothing to do
if (diffs[i] > 0) { // if adding
holds.push(diffs[i]);
continue;
}
// otherwise it's subtracting
t = -diffs[i]; // amount to be subtracted
while (t>0) {
if (t >= holds.top()) {
t -= holds.top();
holds.pop();
res++;
} else { // t < holds.top(), so we kind of decrease the top a little only.
t = holds.top() - t;
holds.pop();
holds.push(t);
break;
}
}
}
cout << res << endl;
return 0;
}
