// Show which combinations of tracks and channels are in use.
#include <stdio.h>
#include <stdlib.h>
#include "h.h"
BP bp;
int main(){note* music = Read("", &bp);
int const tc = bp.trks;
char mp[16][tc];
void fed(note n){
if(n.dur < OpaqueStuff) {
  if(n.chan<1 || n.chan> 16 || !n.trk || n.trk>tc) {
    printf("Bad note chan:%d track:%d \n", n.chan, n.trk); exit(-2);}
  mp[(int)n.chan-1][n.trk-1] = 1;
  }}
{int i=16; while(i--) {int j=tc; while(j--) mp[i][j] = 0;}}
printf("%d tracks\n", bp.trks);
scan(fed, music, 1);
{int i, j;  printf("  ");
for(j=0; j<16; ++j) printf("%3d", j+1); printf("\n");
for(i=0; i<tc; ++i) {
printf("%2d", i+1); for(j=0; j<16; ++j) printf (mp[j][i]?"  *":"   ");
   printf("\n");}}
return 0;}