Minimum Coin Change

minCoinChange.cs

using System;
using System.Collections.Generic;

public class Solution {
    public int CoinChange(int[] coins, int amount) {
       if (amount == 0) return 0;
        if(coins.Length==1){
            if(amount%coins[0]==0)
                return amount/coins[0];
            else
                return -1;
        }
      var r = cc(coins,amount,new Dictionary<int,int>());
        if(r==int.MaxValue)
            return -1;
        return r;
       
    }
    
    public int cc(int[] coins, int amount,Dictionary<int,int> dic) {
       if (amount == 0) return 0;
        if(dic.ContainsKey(amount)){
           return dic[amount];
        }
       int res = int.MaxValue;
       int n = coins.Length;
       for (int i=0; i<n; i++)
       {
         if (coins[i] <= amount)
         {
             int subRes = cc(coins, amount-coins[i],dic);
             if (subRes!= int.MaxValue && subRes + 1 < res)
                res = subRes + 1;
         }
       }
       dic.Add(amount,res);
       return res;
    }
    
    
}