Write a function that returns 2 for input 1 and returns 1 for 2

Last Updated : 23 Jul, 2025

Write a function which returns 1 that 2 is passed and return 2 when 1 is passed.
Source: Adobe Interview Experience | Set 19 (For MTS)
A simple solution is to compare the passed value with 1 and 2.

int invert(int x)
{
   if (x == 1) return 2;
   else return 1;
}

Java

static int invert(int x)
{
   if (x == 1) return 2;
   else return 1;
}

// This code is contributed by rishavmahato348.

Python3

def invert(x):
   if (x == 1):
      return 2
    else:
      return 1

    # This code is contributed by rishavmahato348.

static int invert(int x)
{
    if (x == 1)
        return 2;
    else
        return 1;
}

// This code is contributed by rishavmahato348.

JavaScript

function invert(x)
{
   if (x === 1)
           return 2;
   else
           return 1;
}

// This code is contributed by subham348.

C++

int invert(int x) {
    if (x == 1) {
        return 2;
    }
    else {
        return 1;
    }
}

Another solution is to use subtraction

int invertSub(int x)
{
   return (3-x);
}

Java

static int invertSub(int x)
{
   return (3-x);
}

// This code is contributed by shivanisinghss2110

Python3

def invertSub(x):

   return (3-x)

# this code is contributed by shivanisinghss2110

static int invertSub(int x)
{
   return (3-x);
}

// This code is contributed by subham348.

JavaScript

function invertSub(int x)
{
   return (3-x);
}

// This code is contributed by shivanisinghss2110

C++

int invertSub(int x) {
    return (3 - x);
}

We can also use bitwise xor operator.

int invertXOR(int x)
{
   return (x ^ 1 ^ 2);
}

Java

// JAVA program of the above approach
import java.util.*;
class GFG
{
    
    static int invertXOR(int x)
    {
        return (x ^ 1 ^ 2);
    }
    
     // This code is contributed by sanjoy_62.

}

Python3

# Python3 program to implement the above approach


# This function returns 2 if x is 1
# and vice versa
def invertXOR(x):
    return x ^ 1 ^ 2

# This code is contributed by phasing17

// C# program of the above approach

using System;

class GFG {

    static int invertXOR(int x) { return (x ^ 1 ^ 2); }

    public static void Main(string[] args)
    {
        Console.WriteLine(invertXOR(1));
        Console.WriteLine(invertXOR(2));
    }
}

// This code is contributed by phasing17

JavaScript

// JavaScript program of the above approach

function invertXOR(x)
{
    return (x ^ 1 ^ 2);
}
    

//This code is contributed by phasing17

C++

int invertXOR(int x) {
    return (x ^ 1 ^ 2);
}

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Write a function that returns 2 for input 1 and returns 1 for 2

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