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

Write a function which returns 1 that 2 is passed and return 2 when 1 is passed.

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; 
} 

Another solution is to use subtraction

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

We can also use bitwise xor operator.

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

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