Go: package main

import (
	"bufio"
	"fmt"
	"os"
	"strconv"
)

var infty = 100000 * 2
var scanner = bufio.NewScanner(os.Stdin)

func nextInt() (int, error) {
	scanner.Scan()
	return strconv.Atoi(scanner.Text())
}

func findMaximumSubarray(arr []int) int {
	currentMaxSum, maxSumContainsTail := -infty, -infty

	for j := range arr {
		if arr[j] > maxSumContainsTail+arr[j] {
			maxSumContainsTail = arr[j]
		} else {
			maxSumContainsTail += arr[j]
		}
		if currentMaxSum < maxSumContainsTail {
			currentMaxSum = maxSumContainsTail
		}

		// fmt.Println(arr[j], currentMaxSum, maxSumContainsTail)
	}
	return currentMaxSum
}

func main() {
	scanner.Split(bufio.ScanWords)
	for {
		size, _ := nextInt()
		if size == 0 {
			break
		}

		arr := make([]int, size)
		for i := range arr {
			n, _ := nextInt()
			arr[i] = n
		}

		maximumSum := findMaximumSubarray(arr)
		fmt.Println(maximumSum)
	}
}

C++: #include<iostream>
#include<vector>
int main()
{
	while (!std::cin.eof())
	{
		int n;
		std::cin >> n;
		if (n == 0)
		{
			break;
		}
		std::vector<int>a;
		int max = -100001;
		bool is_all_minus = true;
		for (int i = 0; i < n; i++)
		{
			int foo;
			std::cin >> foo;
			if (foo < 0 && max < foo)
			{
				max = foo;
			}
			is_all_minus &= foo < 0;
			if (i == 0 || a.back() * foo < 0 || a.back() < 0 && foo == 0 || a.back() == 0 && foo < 0)
			{
				a.push_back(foo);
			}
			else
			{
				a.back() += foo;
			}
		}
		if (!is_all_minus)
		{
			if (a.size() == 1)
			{
				max = a[0];
			}
			else
			{
				int begin = a[0] >= 0 ? 0 : 1;
				int temp_max = a[begin];
				try
				{
					for (int i = begin;;)
					{
						if (a.at(i + 1) + a.at(i + 2) > 0)
						{
							temp_max += a[i + 1] + a[i + 2];
							i += 2;
						}
						else
						{
							if (max < temp_max)
							{
								max = temp_max;
							}
							temp_max = a[i + 2];
							i += 2;
						}
					}
				}
				catch (std::out_of_range)
				{
					if (temp_max < a[a.size() - 1])
					{
						temp_max = a[a.size() - 1];
					}
					if (temp_max < a[a.size() - 2])
					{
						temp_max = a[a.size() - 2];
					}
					if (max < temp_max)
					{
						max = temp_max;
					}
				}
			}
		}
		std::cout << max << std::endl;
	}
	return 0;
}

C++: #include<iostream>
#include<string>
#include<cstdio>
#include<algorithm>
#include<stack>
#include<queue>
#include<vector>
#include<cmath>
#define li long int
using namespace std;

int main()
{
  int n,a;
  int i,j;
  int b[5005]={};

  while(1){
    priority_queue<int> pq;
    cin>>n;
    if(n==0)break;
    for(i=1;i<=n;i++){
      cin>>a;
      b[i]=b[i-1]+a;
      for(j=i;j>=0;j--)
	pq.push(b[i]-b[j]);
    }
    cout<<pq.top()<<endl;
  }
}

C++: #include<vector>
#include<iostream>

using namespace std;

int main(){
	while(true) {
		long long int n, tmp;
		cin >> n;
		if (n<=0) {
			//cout << 0 << endl;
			return 0;
		}
		vector<long long int> intervalos;
		intervalos.reserve(n);
		cin >> tmp;
		bool esNegativo = tmp < 0;
		intervalos.push_back(tmp);
		for (int i = 1; i < n; ++i){
			cin >> tmp;
			if (esNegativo == tmp < 0){
				intervalos.back() += tmp;
			} else {
				intervalos.push_back(tmp);
				esNegativo ^= true;
			}
		}
		long long int best = 0;
		long long int current = 0;
		for (int i = 0; i < intervalos.size(); ++i){
			if (intervalos[i]+current <= 0) {
				current = 0;
			} else {
				current+=intervalos[i];
				if (current > best) {
					best=current;
				}
			}
		}
		intervalos.clear();
		cout << best << endl;
		}
	
}

C++: #include <iostream>
#include <vector>
#include <algorithm>
#include <cstdio>
using namespace std;

int main(){
	int n;
	while(cin >> n, n){
		/*n++;
		vector<int> t(n), v(n);
		t[0] = 0;
		for(int i = 1;i < n;i++){
			cin >> v[i];
			t[i] = max(t[i-1]+v[i], v[i]);
		}*/
		vector<int> vec(n),dp(n);
		for(int i=0;i<n;i++)cin >> vec[i];
		dp[0]=vec[0];
		for(int i=1;i<n;i++)dp[i]=max(dp[i-1]+vec[i],vec[i]);
		cout << *max_element(dp.begin(), dp.end()) << endl;
	}
	return 0; 
}

/*
7
-5
-1
6
4
9
-6
-7
*/

C++: #include<iostream>
#include<algorithm>

int main(){

	int n;
	while (std::cin >> n, n){

		int max, before;
		std::cin >> before;

		max = before;

		for (int i = 1, a; i < n; i++){
			std::cin >> a;
			before = std::max(before + a, a);
			max = std::max(max, before);
		}

		std::cout << max << std::endl;
	}

	return 0;
}

C++: #include<iostream>
#include<string>
#include<vector>
using namespace std;

int main() {
	int n, a;
	vector<int> an;
	vector<vector<int>> AN;
	while (cin >> n) {
		if (n == 0)break;
		for (int i = 0; i < n; i++) {
			cin >> a;
			an.push_back(a);
		}
		AN.push_back(an); an.clear();
	}

	for (int i = 0; i < AN.size(); i++) {
		int max = 0, MAX = 0 , counter = 0;
		for (int j = 0; j < AN[i].size(); j++) {
			if (AN[i][j] >= 0) {
				max += AN[i][j];
				if (MAX < max)MAX = max;
				counter = 1;
			}
			else {
				if (counter==1){
					if (AN[i][j] + max >= 0)max += AN[i][j];
					else {
						max = 0;
						counter = 0;
					}
				}
			}
		}
		cout << MAX << endl;
	}
	
	return 0;
}

C++: #include <iostream>
#include <cstring>
using namespace std;
int main(){
	int n;
	while(cin >> n, n){
		int a[5001];
		int ans = -100000;
		for(int i = 0 ; i < n ; i++){
			cin >> a[i];
			if(i){
				a[i] = max(a[i], a[i-1] + a[i]);	
			}
			ans = max(ans, a[i]);
		}
		cout << ans << endl;
	}
	return 0;
}

C++: #include <cstdio>
#include <cstring>
#include <string>
#include <cmath>
#include <cassert>
#include <iostream>
#include <algorithm>
#include <stack>
#include <queue>
#include <vector>
#include <set>
#include <map>
#include <bitset>
#include <functional>
#include <sstream>
#include <utility>
#include <cstdlib>
#include <cctype>
#include <climits>
#include <fstream>

using namespace std;
typedef long long ll;
typedef pair<int, int> pii;
typedef vector<int> vi;
typedef vector<long long> vl;
typedef vector<double> vd;
typedef vector<pair<int, int> > vpii;
#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define rep(i,n) for(int i=0;i<(n);++i)
#define foreach(itr,c) for(__typeof(c.begin()) itr=c.begin(); itr!=c.end(); itr++)
#define dbg(x) cout << #x"="<< (x) << endl
#define mp(a,b) make_pair((a),(b))
#define pb(a) push_back(a) 
#define in(x) cin >> x;
#define all(x) (x).begin(), (x).end()
#define INF 2147483600
#define fi first
#define se second
using namespace std;
int sum[5001];
int main(){
	int N;
	int ans = 0;
	while(cin>>N&&N){
		int index=0;
		ans = INT_MIN;
		FOR(i,1,N+1){
			cin>>sum[i];
			sum[i] += sum[i-1];
		}
		FOR(i,1,N+1){
			FOR(j,i,N+1){
				ans = max(ans,sum[j]-sum[i-1]);
			}
		}
		cout<< ans <<endl;
	}
}

C++: #include <iostream>
#include <vector>
using namespace std;

int main(){
    int n;
    while(cin >> n, n){
        vector<int> a(n,0);
        for(i=0; i<n; ++i){
            cin >> a[n];
        }
        // ????????£?¶??????????????????§??£?¶???????dp??¨?????????
        vector<int> dp(n,0);
        dp[0] = a[0];
        int max = 0;
        for(i=0; i<n; ++i){
            if(dp[i-1]>0){
                dp[i] = dp[i-1] + n[i];
            } else {
                dp[i] = n[i];
            }
            if(max<dp[i]){
                max = dp[i];
            }
        }
        cout << max << endl;
    }
}

C++: #include <iostream>
using namespace std;

int a[5001] = {0};
int S[5001] = {0};

int main() {
  int n;
  while(cin >> n) {
  if(n == 0) break;
  for(int i = 0; i < n; i++) {
    cin >> a[i];
  }

  S[0] = 0;
  for(int i = 1; i <= n; i++) {
    S[i] = S[i-1] + a[i-1];
  }
  

  int maxsum = INT_MIN;
  int sum;
  for(int i = 0; i <= n-1; i++){
    for(int j = i + 1; j <= n;j++) {
      sum = S[j] - S[i];
      if(sum > maxsum)
	maxsum = sum;
    }
  }
  cout << maxsum << endl;
  }
}