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

Recommended: Please try your approach on {IDE} first, before moving on to the solution.

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 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 

Output:

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 
// 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 

Output:

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 
// 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 

Output:

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My Personal Notes

Recommended: Please try your approach on {IDE} first, before moving on to the solution.

C++

C

Java

Python3

C#

C++

C

Java

Python3

C#

C++

C

Java

Python3

C#

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