Create Solution.java

Author: Jerring

solution/0367.Valid Perfect Square/Solution.java

@@ -0,0 +1,9 @@
+class Solution {
+    public boolean isPerfectSquare(int num) {
+        long r = num;
+        while (r * r > num) {
+            r = (r + num / r) / 2;
+        }
+        return r * r == num;
+    }
+}