Comparing two integers without any comparison

Question

Is it possible to find the greatest of two integers without any comparison? I found some solutions:

if(!(a/b)) // if a is less than b then division result          


        

Answer 1

You can use a function to check equal or not using xor bitwise operator. here, you can write this function as:

int Check(int a, int b){
    return (a^b);
}

This function will return 0, if two integers are same, otherwise not.

Here, included an example to understand this function.

Let take two integers as a = 1, b= 2

the bits of 1 is --> 00000001 and for 2 is --> 00000010

if we apply xor operation here, we'll get the result as 00000000 which is 0 in integer. because the xor operations are:

1 xor 1 = 0
1 xor 0 = 1
0 xor 1 = 1
0 xor 0 = 0

Another way you can do by subtracting the number like

int Check(int a, int b)
{
   return abs(a-b);
}

The logic here will work as same as before. If we get 0 then it should be equal otherwise not!