happy_number

hitzzc · hitzzc · commit 11700e33fe32 · 2016-10-16T01:11:04.000+08:00
diff --git a/README.md b/README.md
@@ -160,6 +160,7 @@ Golang solution for leetcode. For each problem, there is a simple *_test.go to t
 #### [199. Binary Tree Right Side View](https://github.com/hitzzc/go-leetcode/tree/master/binary_tree_right_side_view)
 #### [200. Number of Islands](https://github.com/hitzzc/go-leetcode/tree/master/number_of_islands)
 #### [201. Bitwise AND of Numbers Range](https://github.com/hitzzc/go-leetcode/tree/master/bitwise_AND_of_numbers_range)
+#### [202. Happy Number](https://github.com/hitzzc/go-leetcode/tree/master/happy_number)
 
 
 
diff --git a/happy_number/happy_number.go b/happy_number/happy_number.go
@@ -0,0 +1,22 @@
+package happy_number
+
+func isHappy(n int) bool {
+	happened := map[int]bool{}
+	for n != 1 {
+		n = squares(n)
+		if happened[n] {
+			return false
+		}
+		happened[n] = true
+	}
+	return true
+}
+
+func squares(n int) (ret int) {
+	for n > 0 {
+		num := n % 10
+		ret += num * num
+		n /= 10
+	}
+	return
+}
