Find Pattern

#include <stdio.h>

void printHexAndBits(unsigned num){
  printf("%x\t%u\t",num,num);
  int i=1;
  for ( unsigned mask = ~( ~0u >> 1 ); mask ; mask >>= 1, i++ ){
    if ( num & mask){
      putchar('1');
    }
    else {
      putchar('0');
    }

    if (i%4==0){
      putchar(' ');
    }
  }
  putchar('\n');
}

unsigned generateMask(unsigned k){
  return ~(~0u<<k);
}

unsigned findPattern(unsigned num, unsigned numPattern, unsigned patternBits){
  unsigned pattern = numPattern & generateMask(patternBits);
  unsigned patternOccurance=0;

  for (int i=0; i<sizeof(unsigned)*8 - patternBits ; i++){
    if ((num ^ pattern) == (num - pattern)){
      patternOccurance++;
    }
    num>>=1;
  }

  return patternOccurance;
}

int main(){
  unsigned a=0xB6,b=0x36,k=4;
  printf("%u",findPattern(a,b,k));
}