update

added comments and variable names are more simpler now

Author: dpacmen

Misc/root_precision.java

@@ -7,22 +7,27 @@
 public class Solution {
 
     public static void main(String[] args) {
+	//take input    
       Scanner scn = new Scanner(System.in);
 
-      int N = scn.nextInt();
-      int P = scn.nextInt();
+      int N = scn.nextInt(); //N is the input number
+      int P = scn.nextInt(); //P is precision value for eg - P is 3 in 2.564 and 5 in 3.80870.
 
       System.out.println(squareRoot(N, P));
    }
 
    public static double squareRoot(int N, int P) {
-      double sqrt = 0;;
-      
-        // Write your code here
-       double root = Math.pow(N, 0.5);
-		int pre = (int) Math.pow(10, P);
-		root = root * pre;
-	   sqrt =  (int)root;
-      return (double)sqrt/pre;
+        double rv = 0;  //rv means return value
+	   
+        double root = Math.pow(N, 0.5);
+	
+	//calculate precision to power of 10 and then multiply it with root value.
+	int precision = (int) Math.pow(10, P);
+	root = root * precision;
+	 /*typecast it into integer then divide by precision and again typecast into double 
+	   so as to have decimal points upto P precision */ 
+	   
+	rv =  (int)root;
+      return (double)rv/precision;
    }
 }