Реализация целочисленного беззнакового деления

void unsigned_divide(unsigned int dividend,
            unsigned int divisor,
            unsigned int &quotient,
            unsigned int &remainder )
{
 unsigned int t, num_bits;
 unsigned int q, bit, d;
 int i;
 
 remainder = 0;
 quotient = 0;
 
 if (divisor == 0)
   return;
 
 if (divisor > dividend) {
   remainder = dividend;
   return;
 }
 
 if (divisor == dividend) {
   quotient = 1;
   return;
 }
 
 num_bits = 32;
 
 while (remainder < divisor) {
   bit = (dividend & 0x80000000) >> 31;
   remainder = (remainder << 1) | bit;
   d = dividend;
   dividend = dividend << 1;
   num_bits--;
 }
 
 
 /* The loop, above, always goes one iteration too far.
    To avoid inserting an "if" statement inside the loop
    the last iteration is simply reversed. */
 
 dividend = d;
 remainder = remainder >> 1;
 num_bits++;
 
 for (i = 0; i < num_bits; i++) {
   bit = (dividend & 0x80000000) >> 31;
   remainder = (remainder << 1) | bit;
   t = remainder - divisor;
   q = !((t & 0x80000000) >> 31);
   dividend = dividend << 1;
   quotient = (quotient << 1) | q;
   if (q) {
      remainder = t;
    }
 }
}  /* unsigned_divide */
 
 
 
#define ABS(x)  ((x) < 0 ? -(x) : (x))
 
 
 
void signed_divide(int dividend,
          int divisor,
          int &quotient,
          int &remainder )
{
 unsigned int dend, dor;
 unsigned int q, r;
 
 dend = ABS(dividend);
 dor  = ABS(divisor);
 unsigned_divide( dend, dor, q, r );
 
 /* the sign of the remainder is the same as the sign of the dividend
    and the quotient is negated if the signs of the operands are
    opposite */
 quotient = q;
 if (dividend < 0) {
   remainder = -r;
   if (divisor > 0)
     quotient = -q;
 }
 else { /* positive dividend */
   remainder = r;
   if (divisor < 0)
     quotient = -q;
 }
 
} /* signed_divide */