// no of ways to divide the given array into 4 equal parts
import java.util.*;
public class Main
{
	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int n=sc.nextInt();
		int[]nums = new int[n];
		
		for(int i= 0;i<n;i++){
		    nums[i]=sc.nextInt();
		}
		int tot_sum=0;
		for(int i=0;i<n;i++){
		    tot_sum+=nums[i];
		}
		int lhs=0;
		int rhs=0;
		int count=0;
		int count2=0;
		int count_ans=0;
		if(tot_sum%4 ==0){
		    int y=tot_sum/4;
		    
		    //I need current sum 
		    int current_sum=0;
		    
		    HashMap<Integer,Integer>f = new HashMap<>();
		    HashMap<Integer,Integer>g = new HashMap<>();
		    
		    int current_sumg=0;
		    
		    for(int j=n-1;j>=0;j--){
		        current_sumg+=nums[j];
		        g.put(current_sumg,g.getOrDefault(current_sumg,0)+1);
		    }
		    
		    for(int j=0;j<n-1;j++){
		        lhs+=nums[j];
		        rhs=tot_sum-lhs;
		        current_sum+=nums[j];
		        
		        g.put(current_sumg,g.get(current_sumg)-1);
		        if(g.get(current_sumg)==0){
		          g.remove(current_sumg);   
		        }
		        
		        current_sumg-=nums[j];
		        
		        if(lhs == 2*y && rhs ==2*y ){
		          count=count + f.getOrDefault(current_sum/2,0) ;
		          count2=count2 +g.getOrDefault(current_sumg/2,0);
		          count_ans +=count*count2;
		        }
		        f.put(current_sum,f.getOrDefault(current_sum,0)+1);
		    }
		}
		System.out.print("Number of ways to divide in four equal parts :" + count_ans);
	}
}