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

#define pb(n) push_back(n)
#define fi first
#define se second
#define np string::npos
#define X real()
#define Y imag()
#define value(x,y,w,h) (x >= 0 && x < w && y >= 0 && y < h)
#define all(r) (r).begin(),(r).end()
#define gsort(st,en) sort((st),(en),greater<int>())
#define vmax(ary) *max_element(all(ary))
#define vmin(ary) *min_element(all(ary))
#define debug(x) cout<<#x<<": "<<x<<endl
#define fcout(n) cout<<fixed<<setprecision((n))
#define scout(n) cout<<setw(n)

#define rep(i,n) for(int i = 0; i < (int)(n);++i)
#define REP(i,a,b) for(int i = (a);i < (int)(b);++i)
#define repi(it,array) for(auto it = array.begin(),end = array.end(); it != end;++it)
#define repa(n,array) for(auto &n :(array))

typedef long long ll ;
typedef deque<int> di ;
typedef deque<ll> dl ;
typedef map<string,int> dict;
typedef complex<double> comd;
typedef pair<int,int> pii;

constexpr int imax = ((1<<30)-1)*2+1 ;
constexpr int inf = 100000000;
constexpr double PI = acos(-1.0) ;
double eps = 1e-10 ;
const int dy[] = {-1,0,1,0};
const int dx[] = {0,-1,0,1};

double CalcDist(comd p1, comd p2){
  return sqrt(pow(p1.X - p2.X,2.0) + pow(p1.Y -p2.Y,2.0));
}

  template <typename T>
void out(deque < T > d)
{
  for(size_t i = 0; i < d.size(); i++)
  {
    debug(d[i]);
  }
}

template<typename T>
T ston(string& str, T n){
  istringstream sin(str) ;
  T num ;
  sin >> num ;
  return num ;
}

int main(){
  cin.tie(0);
  ios::sync_with_stdio(false);
  int n;
  while(cin >> n){
    if(n == 0) break;
    vector<int> a(n+1,0),b(n+1,0);
    int ans =0,sum=0;
    rep(i,n){
      cin >> a[i];
      sum += a[i];
      b[i+1] = sum;
    }
    rep(i,n+1){
      REP(j,i,n+1){
        ans = max(ans,b[j] - b[i]);
      }
    }
    cout << ans << endl;
  }
  return 0;
}

C++: #include <iostream>
#include <algorithm>
using namespace std;
int main(){
  int n;
  while( cin >> n ,n)
    {
      int a[5101] = {0};
      for(int i = 0 ; i < n ; i++ )
	{
	  cin >> a[i];
	}

      int dp[5101] = {0},mx = 0;

      dp[0] = a[0];
      for(int i = 1 ; i < n ; i++ ){
	dp[i] = max(dp[i-1] + a[i],a[i]); 
	mx = max(dp[i],mx);
      }
      cout << mx << endl;
    }
  return 0;
}

C++: #include <iostream>
using namespace std;
#define N_MAX 5000
int array[N_MAX];
int main(){
	int n;
	int num;
	while(cin>>n&&n){
		int ans=0;
		for(int i=0;i<n;i++){
			cin>>num;
			if(i==0)array[i]=num;
			else{
				array[i]=max(array[i-1]+num,num);
			}
			ans=max(ans,array[i]);
		}
		cout<<ans<<endl;
	}
	return 0;
}

C++: #include <iostream>
#include <algorithm>
#include <climits>
#include <vector>
using namespace std;
typedef long long llong;
typedef vector <llong> vll;

int maxv(vll &x){
	llong tmp=x[0];
	for (int i=1; i<x.size(); i++)
		if (x[i]>tmp) tmp=x[i];
	return tmp;
}

int main(void){
	int n;
	vll x;
	while (cin>>n, n!=0){
		llong s = LLONG_MIN;
		for (int i=0; i<n; i++){
			int n2;
			cin>>n2;

			for (int j=0; j<x.size(); j++){
				x[j] += n2;
			}
			x.push_back(n2);
			llong tmp=maxv(x);
			if (tmp>s) s=tmp;
		}
		cout<<s<<endl;
		x.clear();
	}
	return 0;
}

C++: /*
 * AOJ-Volume0-0022
 */
#include <iostream>
#include <limits.h>
#include <vector>
#include <cstdio>

using namespace std;

typedef long long ll;

/*
 * Find maximum sum.
 *   array: number list
 */
ll findMaximumSum(vector<int> &array){
  ll sumValue = array[0];
  ll maxValue = array[0];
  int length = array.size();

  for(int i = 1; i < length; i++){
    ll value = array[i];

    if(sumValue < 0){
      sumValue = value;
    }else{
      sumValue += value;
    }

    if(maxValue < sumValue){
      maxValue = sumValue;
    }
  }

  return maxValue;
}

void solve(int n){
  vector<int> a(n);

  for(int i = 0; i < n; i++){
    scanf("%d", &a[i]);
  }

  cout << findMaximumSum(a) << endl;
}

int main(){
  int n;

  while(cin >> n){
    if(n == 0) break;

    solve(n);
  }

  return 0;
}

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

int main() {
	int n;
	vector<int> r;
	while (true)
	{
		scanf("%d", &n);
		if (n==0)break;
		int max=INT_MIN,now=0,in=0;
		for (int i=0; i<n; i++)
		{
			cin >> in;
			now += in;
			if (now > max) max=now;
			if (now < 0) now=0;
		}
		r.push_back(max);
	}
	for (int i=0; i<r.size(); i++)
	{
		cout << r[i] << endl;
	}
	return 0;
}

C++: #include<bits/stdc++.h>
#define REP(i,n) for(int i=0;i<n;i++)
#define LOOP(i,x,n) for(int i=x;i<n;i++)
#define ALL(v) (v).begin(),(v).end()
#define PB push_back
#define MP make_pair
#define FR first
#define SC second
#define int long long

using namespace std;
const int MOD=1000000007;
const int INF=9000000009;
const double eps=1e-10;

signed main(){
  int n;
  while(cin>>n,n){
    vector<int> a(n);
    REP(i,n){
      int x;cin>>x;
      a[i+1]=a[i]+x;
    }
    int ans=-INF;
    REP(i,n+1)LOOP(j,i+1,n+1)ans=max(ans,a[j]-a[i]);
    cout<<ans<<endl;
  }
  return 0;
}

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

using namespace std;

int debug = 0;

int main(void){
	int n, m, i, j, k;
	int tmp, max;
	bool first = 0, notAllMinus=0;
	vector<int> intv;

	while(cin >> n){
		if(n == 0){
			break;
		}else{
			//ÇÝÝ
			for(i=0;i<n;i++){
				cin >> m;
				intv.push_back(m);
				//if(debug) cout << "int[" << i << "] =" << intv[i] << endl; 
			}

			//SÌêÌ»è
			tmp = intv[0];
			for(i=0;i<intv.size();i++){
				if(intv[i] > 0){
					notAllMinus = 1;
					break;
				}else{
					if(tmp < intv[i]){
						tmp = intv[i];
					}
				}
			}

			if(notAllMinus == 0){
				cout << tmp << endl;
				intv.clear();
				continue;
			}

			//vfð¸ç·
			tmp=0;
			for(i=1;i<intv.size();i++){
				if(intv[tmp] > 0){
					if(intv[i] > 0){ //¯Èç
						intv[tmp] += intv[i];
						intv[i] = 0;
					}else{ //ÙÈç
						tmp = i;
					}
				}else if(intv[tmp] < 0){
					if(intv[i] < 0){
						intv[tmp] += intv[i];
						intv[i] = 0;
					}else{
						tmp = i;
					}
				}
			}
			
			if(debug){
				for(i=0;i<intv.size();i++){
					cout << intv[i] <<endl;
				}
				cout << "----------------------" << endl;
			}
			
			intv.erase( remove(intv.begin(), intv.end(), 0), intv.end());
			
			if(debug){
				for(i=0;i<intv.size();i++){
					cout << intv[i] <<endl;
				}
			}
			

			int vsize = intv.size();
			for(i=1;i<=vsize;i+=2){//i:Â
				if(debug) cout << "number = " << i << endl;
				for(j=0;j<=vsize-1-i+1;j++){ //j:JnÊu
					tmp = 0;
					for(k=0;k<i;k++){
						tmp += intv[j+k];
					}
					if(debug) cout << "tmp == " << tmp << endl;
					if(first == false){
						max = tmp;
						first = true;
					}else if(max < tmp){
						max = tmp;
					}
				}
			}
			cout << max << endl;
			intv.clear();
			first = false;
			notAllMinus = 0;
		}
	}
	return 0;
}