# include <stdlib.h>
# include <stdio.h>

int main ( int argc, char *argv[] )
{
  int i, n = 1000;
  double x[1000], y[1000], xdoty;

  for ( i = 0; i < n; i++ )
  {
    x[i] = ( double ) rand ( ) / ( double ) RAND_MAX;
    y[i] = ( double ) rand ( ) / ( double ) RAND_MAX;
  }

  xdoty = 0.0;
  for ( i = 0; i < n; i++ )
  {
    xdoty = xdoty + x[i] * y[i];
  }
  printf ( "XDOTY = %e\n", xdoty );
  return 0;
}