how to use min(a,b) in min(a,b,c,d)?

package com.codegym.task.task02.task0217;
/*
Minimum of four numbers
*/
public class Solution {
public static int min(int a, int b, int c, int d) {
return Math.min(Math.min(a,b),Math.min(c,d));
}
public static int min(int a, int b) {
int e = Math.min(a,b);
return e;
}
public static void main(String[] args) throws Exception {
System.out.println(min(-20, -10));
System.out.println(min(-20, -10, -30, -40));
System.out.println(min(-20, -10, -30, 40));
System.out.println(min(-40, -10, -30, 40));
}
}