题目地址：

http://acm.jlu.edu.cn/joj/showproblem.php?pid=1995

我的代码：
#include <iostream>
using namespace std;

int main()
{
int n;
while (cin >> n && n != -1)
{
int a[n+1];
for (int i = 0;i <= n;i ++)
a[i] = 0;

for (int k = 1;k <= n;k ++)
cin >> a[k];
int sum = 0;
int b = 0;

for (int i = 1;i <= n;i ++)
{
if (b > 0) b += a[i];
else b = a[i];
if (b > sum) sum = b;
}
cout << sum << endl;
}
}

一直wa，郁闷

有什么不妥？我自己运行没有错啊

自己再顶上去，求教！问什么不能ac，自己测试了不少数据，没错

那样定义数组好像不行吧
我改了下，结果如下：
#include <iostream>
using namespace std;

int main()
{
int n;
cout<<"input the lenth-1(-1 to end):";
while (cin >> n && n != -1)
{
int *a=new int[n+1];
for (int i = 0;i <= n;i ++)
a[i] = 0;

for (int k = 1;k <= n;k ++)
{
cout<<"input a["
<<k
<<"]:";
cin >> a[k];
}
int sum = 0;
int b = 0;

for ( i = 1;i <= n;i ++)
{
if (b > 0)
b += a[i];
else
b = a[i];
if (b > sum)
sum = b;
}
cout <<"the sum is:"<< sum << endl;
cout<<"input the lenth-1(-1 to end):";
}
return 0;
}
结果
input the lenth-1(-1 to end):4
input a[1]:1
input a[2]:2
input a[3]:3
input a[4]:4
the sum is:10
input the lenth-1(-1 to end):-1