题解 | 看我！

#include <iostream>
#include <cmath>
#include <cstring>
using namespace std;

#define LL long long
#define fas(i,a,b) for(int i=a;i<b;++i) //[)
#define mm  memset
const int MAXN= 1000000;
LL nums[MAXN];
LL dp[MAXN];
int main() 
{
    ios::sync_with_stdio(false);
    int n;  
    while (cin >> n) 
    {
        LL ans=-10000;
        fas(i,0,n)
            cin>>nums[i];
        mm(dp,0,sizeof(int)*n);
        dp[0]=nums[0];
        fas(i,1,n)
            dp[i]=max(nums[i],nums[i]+dp[i-1]);
        fas(i,0,n)
            ans=max(ans,dp[i]);
         cout<<ans<<endl;  
    }
    return 0;
}
// 64 位输出请用 printf("%lld")