#include <bits/stdc++.h>
using namespace std;
using ll = long long;
int main() {
	int n;cin>>n;
	vector<ll>a(n);
	for(int i = 0;i<n;i++){
		cin>>a[i];
	}
	
	
    vector<vector<ll>>dp(n,vector<ll>(100+1,1e18));
    dp[0][a[0]]=0;
    //dp[0][0]=0;
    for(int i = 1 ;i < n ;i++){
    	int sum = 0;
    	for(int j = i ; j >=0;j--){
    		int l = i-j;
    		 sum+=a[j];
    		 if (sum > 100) break;
    		for(int sum1 = 0;sum1<=sum;sum1++){
    	      dp[i][sum] = min(dp[i][sum],(j > 0 ? dp[j-1][sum1] : (sum1 == 0 ? 0 : (ll)1e18)) + l);		
    		}
    	}
    }
    
    long long ans = 1e18;
    for(int i = 0;i<=100;i++){
    	if(dp[n-1][i]<1e18){
    		ans =  min(ans,dp[n-1][i]);
    	}
    }
    cout<<ans;
	return 0;
}