Skip to content

C Program to Check Whether a Number is Positive or Negative or Zero

Program to find absolute value of a given number

Last Updated : 13 Dec, 2023

Given an integer N, The task is to find the absolute value of the given integer.

Examples:

Input: N = -6
Output: 6
Explanation: The absolute value of -6 is 6 which is non negative

Input: N = 12
Output: 12

Naive Approach: To solve the problem follow the below idea:

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

Learn More, Positive and Negative Numbers

Below is the implementation of the above approach.

C++

// C++ program for Method 1 
  
#include <bits/stdc++.h> 
using namespace std; 
  
// Function to find the absolute value 
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 
    cout << " " << N; 
} 
  
// Driver Code 
int 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 value 
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 
    printf("%d ", N); 
} 
  
// Driver Code 
int main() 
{ 
  
    // Given integer 
    int N = -12; 
  
    // Function call 
    findAbsolute(N); 
    return 0; 
} 

Java

// Java program for Method 1 
class GFG{ 
      
// Function to find the absolute value 
static 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 Code 
public 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 value 
def 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 code 
if __name__ == '__main__': 
  
    # Given integer 
    N = -12; 
  
    # Function call 
    findAbsolute(N); 
  
# This is code contributed by amal kumar choubey 

C#

// C# program for Method 1 
using System; 
using System.Collections.Generic; 
  
class GFG{ 
      
// Function to find the absolute value 
static 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 Code 
public 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

Time Complexity: O(1)
Auxiliary Space: O(1)

Find the absolute value of a given number Using Bitmasking:

To solve the problem follow the below idea:

Negative numbers are stored in the form of 2s complement, to get the absolute value we have to toggle bits of the number and add 1 to the result.

Follow the steps below to implement the idea:

Set the mask as right shift of the 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 i.e. mask + n
XOR of mask + n and mask gives the absolute value i.e. [Tex](mask + n)^mask [/Tex]

Below is the implementation of the above approach.

C++

// C++ program for above approach 
  
#include <bits/stdc++.h> 
using namespace std; 
  
// Function to find the absolute 
// value 
void 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 Code 
int 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 
// value 
void 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 Code 
int main() 
{ 
  
    // Given integer 
    int N = -12; 
  
    // Function call 
    findAbsolute(N); 
    return 0; 
} 

Java

// Java program for Method 2 
class GFG{ 
      
static final int CHAR_BIT = 8; 
  
// Function to find the absolute value 
static 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 Code 
public 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 2 
import sys 
  
CHAR_BIT = 8; 
  
# Function to find the absolute value 
def 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 Code 
if __name__ == '__main__': 
      
    # Given integer 
    N = -12; 
  
    # Function call 
    findAbsolute(N); 
  
# This code is contributed by 29AjayKumar 

C#

// C# program for Method 2 
using System; 
  
class GFG{ 
      
static readonly int CHAR_BIT = 8; 
  
// Function to find the absolute value 
static 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 Code 
public 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

Time Complexity: O(1)
Auxiliary Space: O(1)

Find the absolute value of a given number Using the inbuilt abs() function:

To solve the problem follow the below idea:

The inbuilt function abs() in stdlib.h library finds the absolute value of any number. This can be used to find absolute value of any integer.

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 
// value 
void findAbsolute(int N) 
{ 
  
    // Find absolute 
    int X = abs(N); 
  
    // Print the absolute value 
    cout << X; 
} 
  
// Driver Code 
int 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 
// value 
void findAbsolute(int N) 
{ 
  
    // Find absolute 
    int X = abs(N); 
  
    // Print the absolute value 
    printf("%d ", X); 
} 
  
// Driver Code 
int main() 
{ 
  
    // Given integer 
    int N = -12; 
  
    // Function call 
    findAbsolute(N); 
    return 0; 
} 

Java

// Java program for Method 3 
class GFG{ 
      
// Function to find the absolute 
// value 
static void findAbsolute(int N) 
{ 
  
    // Find absolute 
    int X = Math.abs(N); 
  
    // Print the absolute value 
    System.out.printf("%d", X); 
} 
  
// Driver Code 
public 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 3 
import math 
  
# Function to find the absolute 
# value 
def findAbsolute(N): 
  
    # Find absolute 
    X = abs(N); 
  
    # Print the absolute value 
    print(X); 
  
# Driver Code 
  
# Given integer 
N = -12; 
  
# Function call 
findAbsolute(N); 
  
# This code is contributed by Nidhi_biet 

C#

// C# program for Method 3 
using System; 
  
class GFG{ 
      
// Function to find the absolute 
// value 
static void findAbsolute(int N) 
{ 
  
    // Find absolute 
    int X = Math.Abs(N); 
  
    // Print the absolute value 
    Console.Write("{0}", X); 
} 
  
// Driver Code 
public 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

Time Complexity: O(1)
Auxiliary Space: O(1)

C Program to Check Whether a Number is Positive or Negative or Zero

G

geeksforgeeks user

Improve

Article Tags :

Practice Tags :

Similar Reads

Java Program to Check if all digits of a number divide it

Given a number n, find whether all digits of n divide it or not.Examples: Input : 128 Output : Yes 128 % 1 == 0, 128 % 2 == 0, and 128 % 8 == 0. Input : 130 Output : No We want to test whether each digit is non-zero and divides the number. For example, with 128, we want to test d != 0 && 128

C Program to Check for Odd or Even Number

Write a C program to check whether the given number is an odd number or an even number. A number that is completely divisible by 2 is an even number and a number that is not completely divisible by 2 leaving a non-zero remainder is an odd number. Example Input: N = 4Output: EvenExplanation: 4 is div

C Program to Check Whether a Number is Positive or Negative or Zero

Write a C program to check whether a given number is positive, negative, or zero. Examples Input: 10Output: PositiveExplanation: Since 10 is greater than 0, it is positive. Input: -5Output: NegativeExplanation: Since -5 is less than 0, it is negative. Different Ways to Check for Positive Numbers, Ne

How to Find the Range of Numbers in an Array in C?

The range of numbers within an array is defined as the difference between the maximum and the minimum element present in the array. In this article, we will learn how we can find the range of numbers in an array in C. Example Input:int arr[] = { 23, 12, 45, 20, 90, 89, 95, 32, 65, 19 }Output: The ra

Reverse Number Program in C

The reverse of a number means reversing the order of digits of a number. In this article, we will learn how to reverse the digits of a number in C programming language. For example, if number num = 12548, the reverse of number num is 84521. Algorithm to Reverse an IntegerInput: num (1) Initialize re

C++ program for Complex Number Calculator

Pre-Requisites: Complex Numbers, Mathematics, Object-oriented Programming This is a Complex Number Calculator which performs a lot of operations which are mentioned below, to simplify our day-to-day problems in mathematics. The implementation of this calculator is done using C++ Programming Language

Maximize removal of adjacent array elements based on their absolute value

Given an array arr[] of positive and negative integers, the task is to print the array after the removal of adjacent array elements starting from the last index of the array.Array elements can be removed based on the following conditions: Two adjacent elements of opposite sign needs to be compared o

Program that allows integer input only

Given an input value N, the task is to allow taking only integer input from the user. Now, if the user enters any input other than an integer, that is, a character or symbol, it will not be accepted by the program. Below is the C program to implement this approach: [GFGTABS] C // C program for the a

TCS Coding Practice Question | Sum of Digits of a number

Given a number, the task is to find the Sum of Digits of this number using Command Line Arguments. Examples: Input: num = 687 Output: 21 Input: num = 12 Output: 3 Approach: Since the number is entered as Command line Argument, there is no need for a dedicated input lineExtract the input number from

C++ Program to Perform Calculations in Pure Strings

Given a string of operations containing three operands for each operation "type of command", "first operand", and "second operand". Calculate all the commands given in this string format. In other words, you will be given a pure string that will ask you to perform an operation and you have to perfor