I have the right answer got. But i dont understand why i get these Problem ? public class Solution { public static int min(int a, int b, int c, int d) { //write your code here int min; if (a<=b && a<=c && a<=d) min = a; else if (d<=a && d<=b && d<=c) min = d; else if (c<=a && c<=b && c<=d) min = c; else min = b; return min; } public static int min(int a, int b) { //write your code here int min; if (a<=b) min = a; else min = b; return min; } 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)); } }