Write a function in C
int mod(int m, int n) 
that takes exactly two positive integers m, n 
such that m >= n and,
returns 0 if m is a multiple of n else,
returns 1.

Do not use the in-built modulo operator.
Do not use any library functions or floating point operations.
Do not use any additional memory including temporary variables.
Do this in O(1) time complexity.

int mod(int m, int n) { return (n * (m/n) == m); }

m = 3, n = 2; mod(3,2) = 1 // False
m = 4, n = 2; mod(4,2) = 0 // True