懒得开数组了qwq

#include <iostream>

using namespace std;

int n;
int now;
int ans;

int main()
{
    cin >> n;
    for(int i = 1;i <= n;i ++)
    {
        int x;
        cin >> x;
        if(now < x)
        {
            ans += x - now;
            now = x;
        }
        else now = x;
    }
    cout << ans;
    return 0;
}