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 <iostream>
#include <vector>
using namespace std;

int main()
{

	int n, num;
	vector< long int > a;

	while( 1 ) {

		int Max = -1000001;

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

		for( int i = 0; i < n; i++ ) {
		
			cin >> num;
			a.push_back( num );
			
		}

		//?????§???
		for( int i = 1; i <= n; i++ ) {
		
			a[i - 1] + a[i] > a[i] ? a[i] = a[i - 1] + a[i] : a[i] = a[i];

			if ( a[i] > Max ) {
				Max = a[i];
			}
		
		}

		cout << Max << endl;

		a.clear();
	
	}

	return 0;

}

C++: #include<stdio.h>
int main(void){
   int n, a, i, max = 0, sum[100][100];
   scanf("%d", &n);
   for ( i = 0; i < n; i++ ) {
       scanf("%d", &a);
       if ( i == 0 )sum[0][0] = a;
       else sum[0][i] = sum[0][i - 1] + a;
       if ( max < sum[0][i]) max = sum[0][i];
       printf("sum:%d max:%d\n", sum[0][i], max);
   }
   printf("%d", max[0]);
   return 0;
}

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

using namespace std;

int main(){
  int n,x[5000];
  while(1){

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

  for(int i=0; i < n;i++)cin >> x[i];

  int now=0;
  int Max=-100001,tmp;
  for(int i = 0;i < n; i++){
    now+=x[i];
    tmp=now;

    for(int j=0;j < i;j++){
      Max=max(Max,now);
      now-=x[j];
      }

    now=tmp;
    }
  cout << Max << endl;
} 

  return 0;
}

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

int main()
{
	int n;
	while(cin>>n,n)
	{
		int data[n],dp[n+1];
		int tmp=0,ans;
		for (int i = 0; i < n; ++i)
		{
			cin>>data[i];
		}
		dp[0]=data[0];
		for (int i = 1; i < n; ++i)
		{
			dp[i]=max(dp[i-1]+data[i],data[i]);
			ans=max(ans,dp[i]);
		}
		cout<<ans<<endl;
	}
	return 0;
}

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

long long a[5000];
int main(){
	int n;
	while(cin >> n && n){
		long long ans = 1e9;
		for(int i = 0 ; i < n ; i++) cin >> a[i] , ans = min(ans, a[i]);
		long long sub = 0;
		for(int i = 0 ; i < n ; i++){
			sub += a[i];
			if( sub < 0 ){
				sub = 0;
			}else{
				ans = max(ans,sub);
			}
		}
		cout << ans << endl;
	}
}

C++: #include <cstdio>
#include <algorithm>
#include <functional>
#include <stack>
#include <cmath>
using namespace std;

#define REP(i, n) for(int i = 0;i < n;i++)
#define REPR(i, n) for(int i = n;i >= 0;i--)
#define FOR(i, m, n) for(int i = m;i < n;i++)
#define llong long long

int main() {
  while(1){
    int n;
    scanf("%d",&n);
    if(n == 0) break;
    int a[n];
    REP(i,n) scanf("%d",a+i);
    int max = 0;
    int sum = 0;
    REP(i,n) {
      sum += a[i];
      if(max < sum) max = sum;
      if(sum < 0) sum = 0;
    }
    if(max < sum) max = sum;
    printf("%d\n",max);
  }
  return 0;
}

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

#define rep(i, n) for (int i = 0; i < int(n); i++)
#define rrep(i, n) for (int i = int(n) - 1; i >= 0; i--)
#define reps(i, n) for (int i = 1; i <= int(n); i++)
#define rreps(i, n) for (int i = int(n); i >= 1; i--)
#define repc(i, n) for (int i = 0; i <= int(n); i++)
#define rrepc(i, n) for (int i = int(n); i >= 0; i--)
#define repi(i, a, b) for (int i = int(a); i < int(b); i++)
#define repic(i, a, b) for (int i = int(a); i <= int(b); i++)
#define each(x, y) for (auto &x : y)
#define all(a) (a).begin(), (a).end()
#define bit(b) (1ll << (b))

using namespace std;

using i32 = int;
using i64 = long long;
using u64 = unsigned long long;
using f80 = long double;
using vi32 = vector<i32>;
using vi64 = vector<i64>;
using vu64 = vector<u64>;
using vf80 = vector<f80>;
using vstr = vector<string>;

inline void yes() { cout << "Yes" << '\n'; exit(0); }
inline void no() { cout << "No" << '\n'; exit(0); }
inline i64 gcd(i64 a, i64 b) { if (min(a, b) == 0) return max(a, b); if (a % b == 0) return b; return gcd(b, a % b); }
inline i64 lcm(i64 a, i64 b) { return a / gcd(a, b) * b; }
inline u64 xorshift() { static u64 x = 88172645463325252ull; x = x ^ (x << 7); return x = x ^ (x >> 9); }
void solve(); int main() { ios::sync_with_stdio(0); cin.tie(0); cout << fixed << setprecision(16); solve(); return 0; }
template <typename T> class pqasc : public priority_queue<T, vector<T>, greater<T>> {};
template <typename T> class pqdesc : public priority_queue<T, vector<T>, less<T>> {};
template <typename T> inline void amax(T &x, T y) { if (x < y) x = y; }
template <typename T> inline void amin(T &x, T y) { if (x > y) x = y; }
template <typename T> inline T power(T x, i64 n, T e = 1) { T r = e; while (n > 0) { if (n & 1) r *= x; x *= x; n >>= 1; } return r; }
template <typename T> istream& operator>>(istream &is, vector<T> &v) { each(x, v) is >> x; return is; }
template <typename T> ostream& operator<<(ostream &os, vector<T> &v) { rep(i, v.size()) { if (i) os << ' '; os << v[i]; } return os; }
template <typename T, typename S> istream& operator>>(istream &is, pair<T, S> &p) { is >> p.first >> p.second; return is; }
template <typename T, typename S> ostream& operator<<(ostream &os, pair<T, S> &p) { os << p.first << ' ' << p.second; return os; }

void solve() {
  while (true) {
    int n; cin >> n;
    if (n == 0) return;
    vi64 a(n); cin >> a;
    vi64 sums(n + 1);
    rep(i, n) sums[i + 1] += sums[i] + a[i];
    i64 ma = -1e18;
    for (int l = 0; l < n; l++)
    for (int r = l + 1; r <= n; r++) {
      amax(ma, sums[r] - sums[l]);
    }
    cout << ma << '\n';
  }
}

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(x) (x).begin(),(x).end()
#define pb push_back
#define mp make_pair
#define fir first
#define sec second
#define ub upper_bound
#define lb lower_bound
#define int long long
using namespace std;
const int MOD=1000000007;
const int INF=1000000009;

signed main(){
  int n;
  while(cin>>n,n){
    vector<int> v(n+1);
    rep(i,n)cin>>v[i+1];
    rep(i,n)if(v[i]>0)v[i+1]+=v[i];
    cout<<*max_element(v.begin(),v.end())<<endl;
  }
  return 0;
}

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

int main(){

	int n;
	std::cin>>n;

	while(n!=0){

		std::vector<int> a(n);

		for(int i=0;i<n;i++){
			std::cin>>a[i];
		}

		int max=0;

		for(int i=0;i<n-1;i++){
			int sum=0;
			for(int j=0;j<n-i;j++){
				sum+=a[i+j];
				if(sum>max)max=sum;
			}
		}

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

		std::cin>>n;

	}

}

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

using namespace std;

int main(){

  int n;


  while(cin >> n){
    if(n == 0) break;
    vector<int> V;
    int status = 1;
    int in;
    int sum = 0;
    for(int i = 0; i < n; i++){
      cin >> in;
      if(i == 0){
	if(in < 0) status = -1;
	else status = 1;

      } else {	
	if(in < 0 && status == 1){
	  status = -1;
	  V.push_back(sum);
	  sum = 0;
	}else if(in > 0 && status == -1){
	  status = 1;
	  V.push_back(sum);
	  sum = 0;
	}
      }
      sum += in;
    }

    V.push_back(sum);

    int max = -50000000000;
    
    for(int i = 0; i < V.size(); i++){
      sum = 0;
      for(int j = i; j < V.size(); j++){
	sum += V[j];
	if(max < sum) max = sum;
      }
    }
    
    cout << max << endl;
  }
  return 0;
}