Go: package main

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

var scanner = bufio.NewScanner(os.Stdin)

func nextInt() int {
	scanner.Scan()
	i, e := strconv.Atoi(scanner.Text())
	if e != nil {
		panic(e)
	}
	return i
}

func max(x, y int) int {
	if x > y {
		return x
	} else {
		return y
	}
}

func main() {
	sum := make([]int, 5001)
	for {
		n := nextInt()
		if n == 0 {
			break
		}
		for i := 0; i < n; i++ {
			a := nextInt()
			sum[i+1] = sum[i]+a
		}
		ret := sum[1]
		for i := 0; i <= n; i++ {
			for j := i + 1; j <= n; j++ {
				ret = max(ret, sum[j]-sum[i])
			}
		}
		fmt.Println(ret)
	}
}

C++: #include <cassert>
#include <cmath>
#include <iostream>
#include <vector>
#include <algorithm>

int solve(std::istream& in, int n)
{
    std::vector<int> all(n);
    std::vector<int> koho;
    int temp = 0;
    for(int i = 0; i < n; ++i) {
        in >> all[i];
        if(temp && all[i] < 0){
            koho.push_back(temp);
            temp = 0;
        }else
        if(all[i] > 0){
            temp += all[i];
        }
    }
    koho.push_back(temp);
    if(koho.empty()) return *std::min_element(all.begin(), all.end());
    return *std::max_element(koho.begin(), koho.end());
}
int main()
{
    int n;
    std::cin >> n;
    while(n){
        std::cout << solve(std::cin, n) << std::endl;
        std::cin >> n;
    }
    return 0;
}

C++: #include <iostream>
#include <string>
#include <stdlib.h>
#include <fstream>

using namespace std;


int sumarray(int *array, int idx1, int idx2);


int main(){
  int n, Max, ibuf;
  int *List;

  ifstream ifs("input.txt");

  while(ifs >> n){
    if(n == 0) break; // at end condition

    List = new int[n];  // allocate List

    for(int i=0; i<n; i++){
      ifs >> List[i];
      //cout << List[i] << " "; // for debug
    }

    //cout << endl; // for debug

    Max = 0;
    for(int l=1; l<=n; l++){
      for(int i=0; i<=n-l; i++){
	ibuf = sumarray(List, i, i+l);
	if(ibuf > Max) Max = ibuf;
	//cout << ibuf << endl; // for debug
      }
    }

    cout << Max << endl;

    delete List; // deallocate List
  }

}


int sumarray(int *array, int idx1, int idx2){ // sum array[idx1] ~ array[idx2-1]
  int ret = 0;
  for(int i=idx1; i<idx2; i++){
    ret += array[i];
  }
  return ret;
}

C++: /* {{{ Shinobu kawaii */
/*
  ______   __        _                  __                 
.' ____ \ [  |      (_)                [  |                
| (___ \_| | |--.   __   _ .--.   .--.  | |.--.   __   _   
 _.____`.  | .-. | [  | [ `.-. |/ .'`\ \| '/'`\ \[  | | |  
| \____) | | | | |  | |  | | | || \__. ||  \__/ | | \_/ |, 
 \______.'[___]|__][___][___||__]'.__.'[__;.__.'  '.__.'_/ 
                                                           
*/
/* }}} */

#include <bits/stdc++.h>
using namespace std;

// #define int long long

/* cpp template {{{ */

/* short */
#define pb push_back
#define mp make_pair
#define print(x) cout << x << '\n'
#define Fi first
#define Se second

/* REPmacro */
#define REPS(i, a, n) for (int i = (a); i < (n); i++)
#define REP(i, n) for (int i = 0; i < (n); i++)
#define RREP(i, n) for (int i = 1; i <= (n); i++)
#define DEPS(i, a, n) for (int i = (a); i >= n; i--)
#define DEP(i, n) for (int i = (n); i >= 0; i--)

/* typedef */
typedef long long ll;
typedef unsigned long long ull;
typedef vector<int> vi;
typedef vector<vector<int> > vii;
typedef pair<int, int> pii;

/* const */
const int INF = 999999999;
const int dx[] = {0, 1, 0, -1}, dy[] = {1, 0, -1, 0};

/* func */
inline bool is_uruu(int y) {return (y % 4 == 0 && (y % 100 != 0 || y % 400 == 0));}
inline bool inside(int y, int x, int H, int W) {return (y >= 0 && x >= 0 && y < H && x < W);}

/* }}} */

signed main()
{
  ios::sync_with_stdio(false);
  int n;
  while (cin >> n, n){
    vi a(n);
    int ans = -99999999;
    REP(i, n) cin >> a[i];
    REP(i, n){
      int sum = 0;
      REPS(j, i, n){
        sum += a[j];
        ans = max(ans, sum);
      }
    }
    print(ans);
  }

  return (0);
}

C++: #include<iostream>
#include<cstring>
#define N 5001
#define rep(i,n) for(int i=0;i<n;i++)
using namespace std;

int main()
{
    int n;
    while(cin >> n &&n!=0)
    {
        if(n==0)break;
        long int s[N];
        //memset(s,0,sizeof(int)*N);
        int t;
        long int max = -N*100000;
        long int min = 0;
        for(int i=0;i<n;i++){
            cin >>t;
            s[i+1] = s[i]+t;
            if(max<s[i+1])max = s[i+1];
            if(min>s[i+1])min = s[i+1];
        }
        cout << max -min << endl;

    }

    return 0;
}

C++: #include<bits//stdc++.h>
using namespace std;
int main(){
	int n;
	int a[5000];
	while(cin>>n&&n!=0){
		int sum3=0;
		for(int i=0;i<n;i++)
			cin>>a[i];
		for(int i=0;i<n;i++){
			int sum=0;
			int sum2=0;
			for(int j=0;j<=i;j++){
				sum2=0;
				for(int z=j;z<=i;z++){
					sum2+=a[z];
					if(sum<sum2) sum=sum2;
				}
			}
			if(sum3<sum) sum3=sum;
		}
		cout<<sum3<<endl;
	}
}

C++: #include <cstdio>
int main() {
	int n, i, j, s, m, a[5000];
	while (scanf("%d", &n) && n) {
		for (i = 0; i < n; i++) scanf("%d", &a[i]);
		m = -2147483647;
		for (i = 0; i < n; i++, s = 0)
			for (j = i; j < n; j++)
				if ((s += a[j]) > m) m = s;
		printf("%d\n", m);
	}
	return 0;
}

C++: #include<iostream>
using namespace std;
int main()
{
int n;
while(cin>>n&&n!=0)
{
int a[n];
int A=0;
int R=-100000;
for(int h=0;h<n;h++)
{
	cin>>a[h];
}
for(int i=0;i<n;i++)
{
	for(int j=i;j<n;j++)
	{
	//	cout << j << " ";		
		A=A+a[j];
		
	}	
	if(R<A)
	{
		R=A;
	}
	//cout<<endl;
	A=0;
	}
cout<<R<<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[3000];
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<stdio.h>

int main(void)
{
  int a[5010]={};
  int tr;
  int i,j;
  int n;
  int max;

  for(scanf("%d",&n);n;scanf("%d",&n))
    {
      for(i=0;i<5010;i++)a[i]=0;
      max=0x80000000;
      for(i=1;i<=n;i++)
        {
          scanf("%d",&tr);
          a[i]=a[i-1]+tr;
        }
      for(i=0;i<n;i++)
        for(j=i+1;j<=n;j++)
          {
            tr=a[j]-a[i];
            if(max<tr)
              max=tr;
          }
      printf("%d\n",max);
    }

}

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

int main()
{
	int n=1, count = 0;
	int a[10000],ans[10000];
	while (n != 0) {
		cin >> n;
		for (int i = 0; i < n; i++) {
			cin >> a[i];
		}
		int sum = 0, max = -10000,sin=1;
		for (int ai = 0; ai < n - 1; ai++) {
			if (a[ai] > 0 || sin == 0) {
				sin = 0;
				for (int bi = n - 1; bi > ai; bi--) {
					sum = 0;
					for (int k = ai; k < bi; k++) {
						sum = sum + a[k];
					}
					if (sum > max) {
						max = sum;
					}
					//cout << ai << " " << bi << endl;
				}
			}
		}
		ans[count] = max;
		count++;
	}
	for (int ci = 0; ci < count-1; ci++) {
		cout << ans[ci] << endl;
	}
}