#include <stdio.h>

/* Generate some random data for a CSE2304 prac problem */

long rand(int lo, int hi)
/* return a pseudo random number in [lo,hi] */
 { int range;  range = hi-lo+1;
   return lo + random() % range;
 }

gen(int N, int nPerLine, int seed, int lo, int hi)
/* Print N random numbers from [lo,hi], nPerLine of them to the line. */
 { int i;
   if(seed > 0) srandom( seed ); /* to seed it or not? */
   for( i = 1; i <= N; i++)
    { printf("%i", rand(lo, hi));
      if(i % nPerLine == 0 || i == N) printf("\n");
      else printf(" ");
    }
 }/* gen */

pairs(int P, int lo, int hi)
 { int i, p, q, temp;
   for( i = 1; i <= P; i++)
    { p = rand(lo, hi);
      q = rand(lo, hi);
      if( q < p ) /* swap */
       { temp = p; p = q; q = temp; }
      printf("%i %i\n", p, q);
    }
 }

/* ------------------------------------------------------------------------- */

main(int argc,  char *argv[])
{ int N, M, seed, lo, rng;

  if (argc < 4) /* # of command line arguments */
   { printf("error, usage: prog N M seed\n"); exit(1); }

  sscanf(argv[1], "%i", &N);
  sscanf(argv[2], "%i", &M);
  sscanf(argv[3], "%i", &seed);      /* seed  for random */
  if( seed <= 0 ) seed = 1231;

  /*  printf("N = %i, M = %i, seed = %i\n", N, M, seed);   */

  lo = -5; rng = 10;
  for( ; rng < 10000000; )
             /* mttthhh */
   { if( 3*rng >= N ) break;
     lo = lo*10; rng = rng*10;
   }
  gen(N, 10, seed, lo, lo+rng);
  printf("\n");
  pairs(M, 0, N-1);

}
/* L.Allison, CSSE, Monash, .au, January 2004 */