Electronics Shop - Hackerrank Solution

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
class Solution {

   

    static void Main(String[] args) {
        string[] tokens_s = Console.ReadLine().Split();
        int s = int.Parse(tokens_s[0]);
        int n = int.Parse(tokens_s[1]);
        int m = int.Parse(tokens_s[2]);
        
        string[] key = Console.ReadLine().Split();
        int[] keyb = Array.ConvertAll(key,int.Parse);
        string[] drive = Console.ReadLine().Split();
        int[] usb = Array.ConvertAll(drive,int.Parse);
       
        
          int [] arr = new int[m*n];
        int e=0;
        for(int i=0;i<n;i++)
        {
            for(int j=0;j<m;j++)
            {
               arr[e]= keyb [i]+ usb[j]; 
                e++;
            }
        }
            
        int [] brr = new int[m*n];
        for(int q=0;q<m*n;q++)
        {
            brr[q] = s-arr[q];
        }
        
        int ch = 100000000,p=0;
        
        for(int i=0;i<m*n;i++)
        {
            if(brr[i]>=0)
            {
                if(brr[i]<ch)
                {
                    ch = brr[i];
                    p=i;
                }
            }
        }
        
        if(ch==100000000)
        {
            Console.WriteLine("-1");
        }
        
        if(ch != 100000000)
        {
            Console.WriteLine("{0}",arr[p]);
        }
    }
}