upload 1 answer, Aug 18th

Author: stevenlordiam

Diff for: Easy/UglyNumber.java

@@ -0,0 +1,31 @@
+/*
+Write a program to check whether a given number is an ugly number.
+
+Ugly numbers are positive numbers whose prime factors only include 2, 3, 5. For example, 6, 8 are ugly while 14 is not ugly since it includes another prime factor 7.
+
+Note that 1 is typically treated as an ugly number
+*/
+
+public class UglyNumber {
+    public boolean isUgly(int num) {
+        if(num <= 0)    return false;
+        while(num != 1){
+            if(num %2 == 0) {
+                num = num /2;
+            } else if(num % 3== 0) {
+                num = num /3;
+            } else if(num % 5 == 0) {
+                num = num/5;
+            } else{
+                return false;
+            }
+        }
+        return true;
+    }
+}
+
+/*
+http://blog.csdn.net/nisxiya/article/details/46767595
+http://blog.csdn.net/martin_liang/article/details/45692933
+http://blog.csdn.net/u010786672/article/details/44259927
+*/