代码

#include <bits/stdc++.h>
#define gor(A,B,E) for(int A=B;A<=E;++A)
using namespace std;

inline int read() {
	int c,f=1,v=0;while(!isdigit(c=getchar())) if(c=='-')f=-1;
	do v*=10,v+=c-'0'; while(isdigit(c=getchar()));return v;
}

const int N = 1e5+3;

int n, a, mn = 0, ans = 0;

int main() {
	n = read();
	gor(i, 1, n) {
		a = read();
		if (a - mn > 0) ans += a - mn;
		mn = a;
	}
	cout << ans << endl;
	return 0;
}

评测结果