/* Contest  : Problem suggestion for SWERC97/98 at Ulm
 * Problem  : Triangle
 * Method   : save free fields to the left
 * Author   : Gerhard Lutz
 * Date     : September 14th, 1997
 */

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

#define N_MAX 500 /* Maximum value of n */
#define DBG(x)


FILE* input;
int kase=0;

int n;                  /* number of lines per test case */
int best;               /* best solution */
char cw[N_MAX][2*N_MAX+10];  /* input triangle */
int l[N_MAX][2*N_MAX+10];    /* number of white fields to the left of each field */


int read_case()
{
  int i;

  fscanf(input,"%d ",&n);
  if (n==0) return 0;

  for (i=0;i<n;i++) 
    {
      fscanf(input, "%s ", cw[i]);
      DBG(printf("%*s\n", 2*n-i, cw[i]));
    }
  return 1;
}


void solve_case()
{
  int r1,c1,r2;
  int delta_c, delta_r;

  printf("Triangle #%d\n",++kase);

  /* calculate number of white fields to the left
   */
  for (r1=0;r1<n;r1++)          /* row from top to bottom*/
    for (c1=0;cw[r1][c1];c1++)  /* column from left to right*/
      if (cw[r1][c1]=='#')
	/* field is blocked */
	l[r1][c1]=0;
      else if (c1>1 && cw[r1][c1-1]=='-' && cw[r1][c1-2]=='-')
	/* always look two fields back */
	l[r1][c1]=l[r1][c1-2]+1;
      else
	/* the field itself
	 */
	l[r1][c1]=1;
  
  best=0;

  /* for each field where new best solution is possible
   */
  for (r1=0;r1<n-best;r1++)             /* row from top to bottom */
    for (c1=2*(n-r1)-1;c1>=2*best;c1--) /* column from right to left */
      {
	/* calculate biggest triangle where the field is its right edge
	 */
	for (r2=1;l[r1][c1]>best && l[r1][c1]-r2>0;r2++)
	  {
	    /* check if the triangle goes to top or bottom
	     */
	    delta_r = (c1%2==0) ? r2 : -r2;
	    delta_c = (c1%2==0) ? 2*r2 : 0;
	    
	    if (r1+delta_r<0)

	      /* triangle goes to top and out of the
	       * input triangle
	       */
	      l[r1][c1]=r2;

	    else if (l[r1+delta_r][c1-delta_c]+r2<l[r1][c1])

	      l[r1][c1]=l[r1+delta_r][c1-delta_c]+r2;
	  }
	
	/* better solution found ?
	 */
	if (l[r1][c1]>best) best=l[r1][c1];
      }

  /* the solution is the square of 'best'
   * (sum of odd numbers from 1 to 'best')
   */
  printf("The largest triangle area is %d.\n\n",best*best);
}


int main()
{
  input = fopen("triangle.in","r");
  if (input==NULL) 
    {
      printf("Error: can't find input file\n");return 1;
    }

  while (read_case()) solve_case();

  fclose(input);
  return 0;
}