Program to find absolute value of a given number
Given an integer N, the task is to find the absolute value of the given integer.
Examples:
Input: N = -6
Output: 6
Input: N = 12
Output: 12
Method 1 – Naive Approach: Since the absolute value of any number is always positive. For any positive number, the absolute value is the number itself and for any negative number, the absolute value is (-1) multiplied by the negative number.
C++
// C++ program for Method 1#include <bits/stdc++.h>using namespace std;// Function to find the absolute valuevoid findAbsolute(int N){ // If the number is less than // zero, then multiply by (-1) if (N < 0) { N = (-1) * N; } // Print the absolute value cout << " " << N;}// Driver Codeint main(){ // Given integer int N = -12; // Function call findAbsolute(N); return 0;}// This code is contributed by shivanisinghss2110 |
C
// C program for Method 1#include <stdio.h>// Function to find the absolute valuevoid findAbsolute(int N){ // If the number is less than // zero, then multiply by (-1) if (N < 0) { N = (-1) * N; } // Print the absolute value printf("%d ", N);}// Driver Codeint main(){ // Given integer int N = -12; // Function call findAbsolute(N); return 0;} |
Java
// Java program for Method 1class GFG{ // Function to find the absolute valuestatic void findAbsolute(int N){ // If the number is less than // zero, then multiply by (-1) if (N < 0) { N = (-1) * N; } // Print the absolute value System.out.printf("%d ", N);}// Driver Codepublic static void main(String[] args){ // Given integer int N = -12; // Function call findAbsolute(N);}}// This code is contributed by 29AjayKumar |
Python3
# Python3 program for Method 1# Function to find the absolute valuedef findAbsolute(N): # If the number is less than # zero, then multiply by (-1) if (N < 0): N = (-1) * N; # Print the absolute value print(N);# Driver codeif __name__ == '__main__': # Given integer N = -12; # Function call findAbsolute(N);# This is code contributed by amal kumar choubey |
C#
// C# program for Method 1using System;using System.Collections.Generic;class GFG{ // Function to find the absolute valuestatic void findAbsolute(int N){ // If the number is less than // zero, then multiply by (-1) if (N < 0) { N = (-1) * N; } // Print the absolute value Console.Write("{0} ", N);}// Driver Codepublic static void Main(String[] args){ // Given integer int N = -12; // Function call findAbsolute(N);}}// This code is contributed by sapnasingh4991 |
Javascript
<script> // Javascript program for Method 1 // Function to find the absolute value function findAbsolute(N) { // If the number is less than // zero, then multiply by (-1) if (N < 0) { N = (-1) * N; } // Print the absolute value document.write(" " + N); } // Given integer let N = -12; // Function call findAbsolute(N); // This code is contributed by suresh07.</script> |
Output:
12
Method 2 – Using Bitmasking: Since negative numbers are stored in 2s complement form, to get the absolute value, we have to toggle bits of the number and add 1 to the result. Below are the steps:
- Set the mask as right shift of integer by 31 (assuming integers are stored using 32 bits).
mask = n >> 31
- For negative numbers, above step sets mask as 1 1 1 1 1 1 1 1 and 0 0 0 0 0 0 0 0 for positive numbers. Add the mask to the given number.
mask + n
- XOR of mask +n and mask gives the absolute value.
(mask + n)^mask
C++
// C++ program for Method 2#include <bits/stdc++.h>using namespace std;#define CHAR_BIT 8// Function to find the absolute// valuevoid findAbsolute(int N){ // Find mask int mask = N >> (sizeof(int) * CHAR_BIT - 1); // Print the absolute value // by (mask + N)^mask cout << ((mask + N) ^ mask);}// Driver Codeint main(){ // Given integer int N = -12; // Function call findAbsolute(N); return 0;}// This code is contributed by Code_Mech |
C
// C program for Method 2#include <stdio.h>#define CHAR_BIT 8// Function to find the absolute// valuevoid findAbsolute(int N){ // Find mask int mask = N >> (sizeof(int) * CHAR_BIT - 1); // Print the absolute value // by (mask + N)^mask printf("%d ", (mask + N) ^ mask);}// Driver Codeint main(){ // Given integer int N = -12; // Function call findAbsolute(N); return 0;} |
Java
// Java program for Method 2class GFG{ static final int CHAR_BIT = 8;// Function to find the absolute valuestatic void findAbsolute(int N){ // Find mask int mask = N >> (Integer.SIZE / 8 * CHAR_BIT - 1); // Print the absolute value // by (mask + N)^mask System.out.printf("%d ", (mask + N) ^ mask);}// Driver Codepublic static void main(String[] args){ // Given integer int N = -12; // Function call findAbsolute(N);}}// This code is contributed by 29AjayKumar |
Python3
# Python3 program for Method 2import sysCHAR_BIT = 8;# Function to find the absolute valuedef findAbsolute(N): # Find mask mask = N >> (sys.getsizeof(int()) // 8 * CHAR_BIT - 1); # Print the absolute value # by (mask + N)^mask print((mask + N) ^ mask);# Driver Codeif __name__ == '__main__': # Given integer N = -12; # Function call findAbsolute(N);# This code is contributed by 29AjayKumar |
C#
// C# program for Method 2using System;class GFG{ static readonly int CHAR_BIT = 8;// Function to find the absolute valuestatic void findAbsolute(int N){ // Find mask int mask = N >> (sizeof(int) / 8 * CHAR_BIT - 1); // Print the absolute value // by (mask + N)^mask Console.Write((mask + N) ^ mask);}// Driver Codepublic static void Main(String[] args){ // Given integer int N = -12; // Function call findAbsolute(N);}}// This code is contributed by 29AjayKumar |
Javascript
<script> // Javascript program for Method 2 let CHAR_BIT = 8; // Function to find the absolute value function findAbsolute(N) { // Find mask let mask = N >> (4 / 8 * CHAR_BIT - 1); // Print the absolute value // by (mask + N)^mask document.write((mask + N) ^ mask); } // Given integer let N = -12; // Function call findAbsolute(N);// This code is contributed by mukesh07.</script> |
Output:
12
Method 3 – Using inbuilt abs() function: The inbuilt function abs() in stdlib.h library finds the absolute value of any number.
Below is the implementation of the above approach:
C++
// C++ program for Method 3# include<bits/stdc++.h>using namespace std;// Function to find the absolute// valuevoid findAbsolute(int N){ // Find absolute int X = abs(N); // Print the absolute value cout << X;}// Driver Codeint main(){ // Given integer int N = -12; // Function call findAbsolute(N); return 0;}// This code is contributed by Nidhi_biet |
C
// C program for Method 3#include <stdio.h>#include <stdlib.h>// Function to find the absolute// valuevoid findAbsolute(int N){ // Find absolute int X = abs(N); // Print the absolute value printf("%d ", X);}// Driver Codeint main(){ // Given integer int N = -12; // Function call findAbsolute(N); return 0;} |
Java
// Java program for Method 3class GFG{ // Function to find the absolute// valuestatic void findAbsolute(int N){ // Find absolute int X = Math.abs(N); // Print the absolute value System.out.printf("%d", X);}// Driver Codepublic static void main(String[] args){ // Given integer int N = -12; // Function call findAbsolute(N);}}// This code is contributed by sapnasingh4991 |
Python3
# Python3 program for Method 3import math# Function to find the absolute# valuedef findAbsolute(N): # Find absolute X = abs(N); # Print the absolute value print(X);# Driver Code# Given integerN = -12;# Function callfindAbsolute(N);# This code is contributed by Nidhi_biet |
C#
// C# program for Method 3using System;class GFG{ // Function to find the absolute// valuestatic void findAbsolute(int N){ // Find absolute int X = Math.Abs(N); // Print the absolute value Console.Write("{0}", X);}// Driver Codepublic static void Main(String[] args){ // Given integer int N = -12; // Function call findAbsolute(N);}}// This code is contributed by 29AjayKumar |
Javascript
<script> // Javascript program for Method 3 // Function to find the absolute // value function findAbsolute(N) { // Find absolute let X = Math.abs(N); // Print the absolute value document.write(X); } // Given integer let N = -12; // Function call findAbsolute(N);</script> |
Output:
12
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