You are given an array of integers.
You need to find the contiguous subarray of the maximum sum in . The subarray should not contain the number . Please find the maximum sum that is possible.

Note 1: The subarray can also be empty.
Note 2: The answer will fit in 32 bit-signed integer.

Input Format

The first line contains the integer . The next line contains integers representing the numbers in the array.

Constraints

Output Format

Output a single line representing the maximum sum that can be obtained.

Sample Input

5
3 4 0 1 2
Sample Output

7
Explanation

The subarray with the maximum sum that doesn’t contain a is .
Hence, the sum is.

题目大意：

求不包括元素0的最大子序列和。

题目解析：

遍历序列，当遍历到第i个元素时，判断前面的连续子序列的和是否大于0，有就加上；遍历到0元素时，自动清零。

具体代码：

#include<iostream>
#include<algorithm>
#include<vector>
using namespace std;
#define MAXN 100010
int A[MAXN];

int main() {
	int n;
	scanf("%d",&n);
	for(int i=0;i<n;i++)
		cin>>A[i];
	int maxSum=0,maxHere=0;
	for(int i=0;i<n;i++){
		if(A[i]==0)
			maxHere=0;
		else if(maxHere<=0)
			maxHere=A[i];
		else
			maxHere+=A[i];
		maxSum=max(maxHere,maxSum);
	}
	cout<<maxSum<<endl;
	return 0;
}