[69] x 的平方根

src/leecode/javascript/69.x-的平方根.js

@@ -0,0 +1,21 @@
+/*
+ * @lc app=leetcode.cn id=69 lang=javascript
+ *
+ * [69] x 的平方根 
+ */
+
+// @lc code=start
+/**
+ * @param {number} x
+ * @return {number}
+ */
+var mySqrt = function(x) {
+  let ret = 1;
+  while (ret * ret < x) {
+    ret += 1;
+  }
+  if (ret * ret > x) ret -= 1;
+  return ret;
+};
+// @lc code=end
+