Program to find absolute value of a given number
- Difficulty Level : Basic
- Last Updated : 21 Jun, 2022
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
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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
(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:12
Time Complexity: O(1)
Auxiliary Space: O(1)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 >> 312. 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 + n3. 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
((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:12
Time Complexity: O(1)
Auxiliary Space: O(1)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
(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:12
Time Complexity: O(1)
Auxiliary Space: O(1)My Personal Notes arrow_drop_upRecommended ArticlesPage :Article Contributed By :Improved By :Practice Tags :