子串和

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#include <iostream>
#include <string>
#include <stack>
#include <set>
#include <memory.h>
#include <map>
#include <iomanip>
#include <queue>
#include <algorithm>

#define max(a,b) (a>b ? a:b)
using namespace std;

int dp[1000001];
int arr[1000001];
int main()
{
    int n;
    int t;
    cin >> t;
    while (t--)
    {
        cin >> n;
        int flag = 0;
        int M = -99999999;
        for (int i = 0; i < n; i++)
        {
            cin >> arr[i];
            if (arr[i]>0)
                flag = 1;
            if (arr[i] > M)
                M = arr[i];
        }
        if (flag == 0)
        {
            cout << M << endl;
            continue;
        }

        memset(dp, 0, sizeof(dp));
        dp[0] = arr[0];
        int Max = -9999999;
        for (int i = 1; i < n; i++)
        {
            if (dp[i - 1] >= 0)
                dp[i] = dp[i - 1] + arr[i];
            else
                dp[i] = arr[i];

            if (dp[i]>Max)
                Max = dp[i];
        }

        cout << Max<< endl;
    }
    return 0;
}