CODE

public class Solution {
  public int MaxProfit(int[] prices) {

    int window_size = 1;
    int max_profit = 0;

    int i = 0;
    int j = i + window_size;

    while (window_size < prices.Length)
    {
      while (j < prices.Length)
      {
        if ((prices[j] - prices[i]) > max_profit)
          max_profit = prices[j] - prices[i];
        j++;
        i++;
      }
      window_size++;
      i = 0;
      j = i + window_size;
    }
    return max_profit;
  }
}