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 <queue>
#include <algorithm>

using namespace std;

int main() {
    while(true) {
        int N;
        cin >> N;
        if(!N) break;

        queue<int> q;
        int ans = 0;
        int sump = 0, sumn = 0;
        int left = 0;
        while(N--) {
            int n;
            cin >> n;
            q.push(n);
            if(n >= 0) sump += n;
            else sumn += -n;
            while(!q.empty() && sump <= sumn) {
                int np = q.front();
                if(np >= 0) sump -= np;
                else sumn -= -np;
                q.pop();
            }
            ans = max(ans, sump-sumn);
        }
        cout << ans << endl;
    }
    return 0;
}

C++: #include <iostream>
#include <algorithm>
#define N 5000
using namespace std;

int main(){
  int n, num, a, maxx;
  int ans[N], ac;
  ac = 0;

  while(cin >> n){
    if(n==0){
      ans[ac] = 0;
      break;
    }

    num = maxx = 0;

    for(int i=0;i<n;i++){
      cin >> a;
      num += a;
      if(num<0) num = 0;
      maxx = max(maxx,num);
    }
    ans[ac] = maxx;
    ac++;
  }

  for(int i=0;ans[i]!=0;i++)
    cout << ans[i] << endl;

  return 0;
}

C++: #include <functional>
#include <algorithm>
#include <iostream>
#include <numeric>
#include <iomanip>
#include <utility>
#include <cstdlib>
#include <sstream>
#include <bitset>
#include <vector>
#include <cstdio>
#include <ctime>
#include <queue>
#include <deque>
#include <cmath>
#include <stack>
#include <list>
#include <map>
#include <set>

using namespace std;

typedef vector<int> vi;
typedef pair<int,int> pii;
typedef long long ll;

#define dump(x)  cerr << #x << " = " << (x) << endl
#define rep(i,n) for(int i=0;i<(n);i++)
#define all(a)  (a).begin(),(a).end()
#define pb push_back


int main() {
    int n;

    while(cin>>n){

        if(n==0)break;
        int data[10000]={};
        rep(i,n) cin>>data[i];

    
        int maxi=-999999999;
        int dp[5000][5001]={};
        rep(i,n){
            for(int j=i;j<n+1;j++){
                if(j-1>=0){
                    dp[i][j]=dp[i][j-1]+data[j-1];
                    maxi=max(maxi,dp[i][j]);
                }
            }
        }
        cout<<maxi<<endl;
    }
    return 0;
}

C++: #include <iostream>
#include <vector>
#include <limits.h>
using namespace std;
int main()
{
	int n, k, p;
	bool isPlus = true;
	while (cin >> n){
		if (0 == n) break;
		vector<int> A(n, 0);
		int m = INT_MIN;
		p = 0;
		for (int i = 0; i < n; ++i){
			cin >> k;
			if (0 == i){
				A[p] = k;
				isPlus = (k > 0);
			}
			else {
				if (isPlus == (k > 0)){
					A[p] += k;
				}
				else{
					if (isPlus == (k > 0)){
						A[p] += k;
					}else{
						++p;
						A[p] = k;
						isPlus = !isPlus;
					}
					while (1 < p && isPlus){
						if (m < A[p - 2]) m = A[p - 2];
						if (m < A[p]) m = A[p];
						int a = A[p - 2] + A[p - 1] + A[p];
						if ((a > A[p - 2]) && (a > A[p])){
							A[p - 2] += A[p-1] + A[p];
							A[p - 1] = A[p] = 0;
							p -= 2;
						}
						else break;
					}
					if (m < A[p]) m = A[p];
				}
			}
		}
		if (m < A[p]) m = A[p];
		cout << m << "\n";
	}
	return 0;
}

C++: #include <stdio.h>
#include <algorithm>
using namespace std;

int main(){
	int num[5000],sum[5001],n,i,res;
	while(1){
		sum[0] = 0;
		scanf("%d",&n);
		if(!n) break;
		for(i = 0;i < n;i++){
			scanf("%d",&num[i]);
			sum[i + 1] = sum[i] + num[i];
		}
		sort(sum,sum + n + 1);
		res = sum[n] - sum[0];
		if(res == -0) res = 0;
		printf("%d\n",res);
	}
	return 0;
}

C++: #include <bits/stdc++.h>

using namespace std;

int s[5001];

int main()
{
    int n;

    while (cin >> n, n) {
        memset(s, 0, sizeof(s));

        for (int i = 1; i <= n; ++i) {
            int a; cin >> a;
            s[i] = a + s[i - 1];
        }

        int ma = INT_MIN;

        for (int i = 1; i <= n; ++i) for (int j = 1; j <= i; ++j) {
            ma = max(ma, s[i] - s[j - 1]);
        }

        cout << ma << endl;
    }
}

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

int main(){
  int i,j,n,max,sum,a[5001];
  while(1){
    cin>>n;
    if(n==0)break;
    for(i=0;i<n;i++){
      cin>>a[i];
    }
    max=0;
    for(i=0;i<n;i++){ 
      sum=0;
      for(j=i;j<n;j++){
	sum+=a[j];
	if(max<sum)max=sum;	
      }
    }
    cout<<max<<endl;
  }
  return 0;
}

C++: #include <iostream>
#include <sstream>
#include <string>
#include <vector>
#include <stack>
#include <queue>
#include <deque>
#include <set>
#include <map>
#include <algorithm>
#include <functional>
#include <numeric>
#include <utility>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <cmath>
#include <ctime>
using namespace std;

typedef long long ll;
typedef pair<int, int> P;

#define all(c) (c).begin(), (c).end()
#define pb push_back
#define mp make_pair
#define EXIST(v,i) (find(all(v), i) != (v).end())
#define ERASE(v,i) (v).erase(remove(all(v), i), (v).end())
#define INDEX(v,i) (find(all(v), i) - (v).begin())
#define rep(i,n) for(int i = 0; i < (int)n; ++i)
#define debug(x) cerr << #x << " = " << (x) << endl;

inline int toInt(string s) {int v; istringstream sin(s);sin>>v;return v;}
template<class T> inline string toString(T x) {ostringstream sout;sout<<x;return sout.str();}

const int INF = 100000000;
const double PI = 3.14159265358979323846;
const double EPS = 1e-10;

int main() {
	for(int n; cin >> n && n;) {
		vector<int> arr(n);
		vector<int> cur(n);
		rep(i,n) cin >> arr[i];
		if(arr[0] > 0) cur[0] = arr[0];
		for(int i = 1; i < n; i++)
			cur[i] = max(arr[i], cur[i - 1] + arr[i]);
		cout << *max_element(all(cur)) << endl;
	}
	return 0;
}

C++: #include <iostream>
#include <cmath>
#include <vector>
using namespace std;
int main(){
  

  int dataSets;

  while(true){
    vector<int> a;
    cin >> dataSets;
    for(int i=0;i<dataSets;i++){
      int tmpa;
      cin >> tmpa;
      a.push_back(tmpa);
      // cout << "a[" << i << "]: " << a[i] << endl;
    }

    int max=0;
    
    for(int i=0;i<dataSets;i++){
      // i+1?????£?¶?
      for(int j=0;j<dataSets-i;j++){
	int tmp=0;
	for(int k=0;k<i+1;k++){
	  tmp += a[j+k];
	  // cout << "(i,j,k): " << i << "," << j << "," << k << "  " << "a[" << j+k << "]   max:" << max << endl;
	}
	if(tmp>max){max=tmp;}
      }
    }
    
    cout << max << endl;
    
  }

  return 0;

}