/* ***********************************************
Author        :guanjun
Created Time  :2016/8/2 12:04:29
File Name     :p512.cpp
************************************************ */
#include <iostream>
#include <cstring>
#include <cstdlib>
#include <stdio.h>
#include <algorithm>
#include <vector>
#include <queue>
#include <set>
#include <map>
#include <string>
#include <math.h>
#include <stdlib.h>
#include <iomanip>
#include <list>
#include <deque>
#include <stack>
#define ull unsigned long long
#define ll long long
#define mod 90001
#define INF 0x3f3f3f3f
#define maxn 1000010
#define cle(a) memset(a,0,sizeof(a))
const ull inf = 1LL << 61;
const double eps=1e-5;
using namespace std;
priority_queue<int,vector<int>,greater<int> >pq;
struct Node{
    int x,y;
};
struct cmp{
    bool operator()(Node a,Node b){
        if(a.x==b.x) return a.y> b.y;
        return a.x>b.x;
    }
};

bool cmp(int a,int b){
    return a>b;
}
int a[maxn];
int vis[maxn];
int main()
{
    #ifndef ONLINE_JUDGE
   // freopen("in.txt","r",stdin);
    #endif
    //freopen("out.txt","w",stdout);
    int n;
    while(cin>>n){
        int mark=0;
        cle(vis);
        for(int i=1;i<=n;i++){
            scanf("%d",&a[i]);
            if(a[i]<0)mark=1,vis[i]=1;
        }
        if(!mark){
            printf("%d\n",n);continue;
        }
        ll ans=0;
        for(int i=n;i>=1;i--){
            if(vis[i]){
                ll sum=a[i];
                while(sum<0){
                    i--;
                    sum+=a[i];
                }
            }
            ans++;
        }
        printf("%I64d\n",ans);
    }
    return 0;
}