Create 0069-sqrtx.kt

Author: a93a

kotlin/0069-sqrtx.kt

@@ -0,0 +1,42 @@
+/*
+* Binary Search
+*/
+class Solution {
+    fun mySqrt(x: Int): Int {
+        var left = 0L
+        var right = x.toLong()
+        var res = 0L
+
+        while (left <= right) {
+            val mid = left + (right - left) / 2
+            val midSq = mid * mid
+            
+            if (midSq > x) {
+                right = mid - 1
+            } else if (midSq < x) {
+                left = mid + 1
+                res = mid
+            } else {
+                return mid.toInt()
+            }
+        }
+
+        return res.toInt()
+    }
+}
+
+/*
+* Newton's method
+*/
+class Solution {
+    fun mySqrt(x: Int): Int {
+        if (x == 0) return 0
+
+        var i = x.toLong()
+        while (i > x / i) {
+            i = (i + x / i) / 2
+        }
+
+        return i.toInt()
+    }
+}