unsigned int umultiply(unsigned int a, unsigned int b) {
   int out = 0;
   int binaryA[8 * sizeof(unsigned int)];
   int binaryB[8 * sizeof(unsigned int)];
   unsigned int final = 0;
   int size = 8 * sizeof(unsigned int);
   for(int i = 0; i < size; i++) {
      binaryA[size - i - 1] = (a >> i) & 1;
      binaryB[size - i - 1] = (b >> i) & 1;
   }

   for(int i = size - 1; i >= 0; i--) {
      if((a >> i) & 1) {
         final += b;
      }
      final = final << 1;
   }
   final = final >> 1;
   return final;
}