代码

#include <bits/stdc++.h>
using namespace std;

#define MAXN 100050
int n, a[MAXN];

int main() {
	cin >> n;
	for (int i = 0; i < n; i++)
		cin >> a[i];
		
	int prev = 0, ans = 0;
	for (int i = 0; i < n; i++) {
		if (a[i] > prev) ans += a[i] - prev;
		prev = a[i];
	}
	
	cout << ans << endl;
	return 0;
}

评测结果