plz help...stuck from 1 day

public class Solution {

  // this returns the min of two numbers, needs to be 4 numbers
   public static int min(int a, int b, int c, int d) {
        if (c<d)
        return c;
        else
        return d;
      // ↑ this code only returns the larger of c and d. It also needs to figure
      // in a and b.
    }


    public static int min(int a, int b) {
        if (a<b)
        return a;
        else
        return b;
      // This returns the min of 2 numbers
    }

    public static void main(String[] args) throws Exception {
        System.out.println(min(-20, -10)); // this calls min(a, b)
        System.out.println(min(-20, -10, -30, -40)); // this calls min(a, b, c ,d)
        System.out.println(min(-20, -10, -30, 40)); // same
        System.out.println(min(-40, -10, -30, 40));  // same
    }
}