3

Author: kedebug

Sqrt(x)/Sqrt(x).cpp

@@ -0,0 +1,20 @@
+class Solution {
+public:
+    int sqrt(int x) {
+        // Start typing your C/C++ solution below
+        // DO NOT write int main() function
+        long long lf = 0;
+        long long rt = x;
+        while (lf <= rt) {
+            long long m = (lf + rt) >> 1;
+            long long sq = m * m;
+            if (sq == (long long)x)
+                return m;
+            else if (sq < (long long)x)
+                lf = m + 1;
+            else 
+                rt = m - 1;
+        }
+        return (int)rt;
+    }
+};