Implement Sqrt function using binary search - The Coding Shala

Home >> Interview Questions >> Implement sqrt()

Implement Sqrt function using binary search

In this post, you will learn how to find the square root of a given number using the binary search algorithm. In java, the sqrt() function is already available to find square root for a number but in this post, we are going to implement sqrt() function using binary search.

Compute and return the square root of x, where x is guaranteed to be a non-negative integer. Since the return type is an integer, the decimal digits are truncated and only the integer part of the result is returned.
Example 1:
Input: 4
Output: 2

Example 2:
Input: 8
Output: 2
Explanation: The square root of 8 is 2.82842..., and since the decimal part is truncated, 2 is returned.

Sqrt function in Java

We can do this using a binary search. If we check one by one until reaching the target we might get time limit error for large numbers.
Java Program: 

class Solution {
    public int mySqrt(int x) {
        if(x==1) return 1;
        int left = 1;
        int right = x/2;
        while(left<=right){
            int mid = left + (right-left)/2;
            if((long)mid*mid == (long)x) return mid;
            if((long)mid*mid > (long)x) right = mid-1;
            else left = mid+1;
        }
        return left-1;
    }
}


Other Posts You May Like
Please leave a comment below if you like this post or found some error, it will help me to improve my content.

By

Comments

Post a Comment

Popular Posts from this Blog

Shell Script to find sum, product and average of given numbers - The Coding Shala

Home >> Scripting >> Sum, product and average Shell Script to find the sum, product, and the average of given numbers Read four integer numbers from the user and find the sum, product, and average of these four numbers? Code:  #! / bin / bash echo "enter four integers" read a b c d sum =$(echo "$a + $b + $c + $d" | bc - l) average=$(echo "$sum / 4" | bc - l) product=$(echo "$a * $b * $c * $d" | bc - l) echo "sum = $sum" echo "Average = $average" echo "Product = $product" Other Posts You May Like Shell script to print sum of the digits of a number Shell Script to print number in descending order Shell script to find out biggest number from three numbers Shell script to find out factorial of a number Shell Script to create a simple calculator Please leave a comment below if you like this post or found some error, it will help me to improve my content.
Read more

Add two numbers in Scala - The Coding Shala

Home >> Learn Scala >> Add Two Numbers  In this post, we will learn how to write a Scala program to Add Two Numbers. Add Two Numbers in Scala The following is the Scala program to Add two Numbers. Scala Program:  //add two numbers in scala //the coding shala object Main { def main ( args : Array [ String ]){ //we can take user input also val num1 = 10 ; val num2 = 20 ; //add both numbers val result = num1 + num2 ; println ( "Sum of " + num1 + " + " + num2 + " = " + result ); } } Other Posts You May Like Scala - Hello World Program Java - Hello World Program Power of Two Simple XML Validator Fibonacci Series Please leave a comment below if you like this post or found some errors, it will help me to improve my content.
Read more

Shell Script to Create a Simple Calculator - The Coding Shala

Home >> Scripting >> simple calculator Shell Script to Create a Simple Calculator Write a shell script to create a simple calculator using a switch-case statement? Code:  #! / bin / bash echo "simple calculator" sum = 0 i = "y" echo "enter first number" read n1 echo "enter second number" read n2 while [ $ i = "y" ] do echo "1.Addition" echo "2.Subtraction" echo "3.Multiplication" echo "4.Division" echo "Enter choice" read ch case $ch in 1 ) sum =$(echo " $n1 + $n2" | bc - l) echo "Addition is =" $ sum ;; 2 ) sum =$(echo "$n1 - $n2" | bc - l) echo "Sub is =" $ sum ;; 3 ) sum =$(echo "$n1 * $n2" | bc - l) echo "Mul is =" $ sum ;; 4 ) sum =$(echo "$n1 / $n2" | bc - l) echo "div is =" $ sum ;; * )echo "invalid choice" esac echo "Do y
Read more

Goal Parser Interpretation LeetCode Solution - The Coding Shala

Home >> LeetCode >> Goal Parser Interpretation  In this post, we will learn how to solve LeetCode's Goal Parser Interpretation Problem and will implement its solution in Java. Goal Parser Interpretation Problem You own a Goal Parser that can interpret a string command. The command consists of an alphabet of "G", "()", and/or "(al)" in some order. The Goal Parser will interpret "G" as the string "G", "()" as the string "o", and "(al)" as the string "al". The interpreted strings are then concatenated in the original order. Given the string command, return the Goal Parser's interpretation of the command. Example 1: Input: command = "G()(al)" Output: "Goal" Explanation: The Goal Parser interprets the command as follows: G -> G () -> o (al) -> al The final concatenated result is "Goal". Example 2: Input: command = "G()()()()(al)&qu
Read more

New Year Chaos Solution - The Coding Shala

Home >> Programming Questions >> New Year Chaos New Year Chaos Problem Solution In this post, you will learn how to solve New Year Chaos Problem and implement its solution in Java. Problem:   It's New Year's Day and everyone's in line for the Wonderland rollercoaster ride! There are a number of people queued up, and each person wears a sticker indicating their initial position in the queue. Initial positions increment from at the front of the line to at the back.  Any person in the queue can bribe the person directly in front of them to swap positions. If two people swap positions, they still wear the same sticker denoting their original places in line. One person can bribe at most two others.  For Example, if n=8 and Person 5 bribes Person 4, the queue will look like this: 1,2,3,5,4,6,7,8. Fascinated by this chaotic queue, you decide you must know the minimum number of bribes that took place to get the queue into its current state. Input:
Read more