Problem in loop. Please Help. Urgent!!

[jjbuchan]

The code below will print out:

Row: 0, Col: 0, p: 0, m: 0
Row: 0, Col: 1, p: 0, m: 0
Row: 0, Col: 2, p: 0, m: 0

Row: 1, Col: 0, p: 0, m: 0
Row: 1, Col: 1, p: 0, m: 0
Row: 1, Col: 2, p: 0, m: 0

Row: 2, Col: 0, p: 0, m: 0
Row: 2, Col: 1, p: 0, m: 0
Row: 2, Col: 2, p: 0, m: 0

Row: 0, Col: 3, p: 3, m: 0
Row: 0, Col: 4, p: 3, m: 0
Row: 0, Col: 5, p: 5, m: 0
Row: 0, Col: 6, p: 5, m: 0
Row: 0, Col: 7, p: 5, m: 0

etc.

Can someone please let me know why p suddenly changes to 5 (everything is fine before that). This is really annoying me and has to be sorted tonight.

Thanks in advance.

int row, col, n, m, p, q;
  Cellgroup cgroup;
  Coord co;
  m = 0; 
  p = 0;
  q = 0;
  n = 0;


while(m<=6) {
      while(p<=6) {
          for(row=m; row<m+3; row++) {
              for(col=p; col<p+3; col++) {
                  co.r = row;
                  co.c = col;
                  cgroup.grp[q] = co;
                  q++;
                  printf("Row: %d, Col: %d, p: %d, m: %d\n",row, col, p, m); 
              }
              printf("\n");
          }
          group[n] = cgroup;
          n++;
          p+=3;
      }
      p=0;
      m+=3;
  }

 

[xwb]

What is cellgroup defined as? At a guess, q has exceeded the bounds of the array and started overwriting the rest of the local variables in the stack.

 

[ArkM]

See your snippet:

  p = 0;
...
  while(p<=6) {
     ....
     p = 0;
  }

Of course, it's loop forever...

 

[jjbuchan]

Nevermind I sorted it.

There wasn't a never ending loop. It was that q would go upto 81, but the max stored within grp is 9.

A simple q = 0 in the right place solved it.

 

[ArkM]

Sorry, p=0 was after loop. I was wrong...