69. x 的平方根

 1 package leetcode;
 2 
 3 public class demo_69 {
 4     public int mySqrt(int x) {
 5         long t=x;
 6         while(t*t>x) {
 7             t=(t+x/t)/2;
 8         }
 9         return (int)t;
10     }
11     public static void main(String[] args) {
12         // TODO Auto-generated method stub
13         demo_69 d69=new demo_69();
14         System.out.println(d69.mySqrt(5));
15     }
16 
17 }