51nod--1049 最大子段和

题目链接：

            http://www.51nod.com/onlineJudge/questionCode.html#!problemId=1049

代码：

#include<iostream>#include<cstdio>#include<algorithm>using namespace std;typedef long long llint;const int MAX=50005;int a[MAX];int main(){    int n;    llint sum=0,maxn=-1;    cin>>n;    for(int i=1;i<=n;i++)        cin>>a[i];    for(int i=1;i<=n;i++)    {        if(sum>0)            sum+=a[i];        else            sum=a[i];        if(maxn<sum)            maxn=sum;    }    cout<<maxn<<endl;    return 0;}