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


# define REP(i,a,b) for(i = a ; i<= b ; i++) 


typedef long long ll ; 
ll MOD = 0x7fffffff ; 
int n ; 
char graph[1010][1010] ; 
int vis[1010][1010] ; 
ll dp[1010][1010] ; 
int q[1010*1010][2] ; 
int tab[4][2] = {{0,-1},{0,1},{-1,0},{1,0}} ; 


void bfs() 
{
int i, x, y, xx, yy ; 
int front = 0, rear = 1 ; 
if (graph[1][1] == '#') return ; 
memset (vis, 0, sizeof(vis)) ; 
vis[1][1] = 1 ; 
q[0][0] = q[0][1] = 1 ; 
while (front != rear) 
{
x = q[front][0], y = q[front][1] ; 
front ++ ;
if (x == n && y == n) return ; 

for(i = 0 ;i < 4 ; i++) 
{
xx = x + tab[i][0] ; 
yy = y + tab[i][1] ; 
if (xx < 1 || xx > n) continue ; 
if (yy < 1 || yy > n) continue ; 
if (vis[xx][yy] == 1) continue ; 
if (graph[xx][yy] == '#') continue ; 
vis[xx][yy] = 1 ; 
q[rear][0] = xx, q[rear][1] = yy ; 
rear++ ;
}
}
}


int dfs(int x, int y) 
{
long long ans = 0 ; 
if (x < 1 || x > n || y < 1 || y > n) return 0 ; 
if (dp[x][y] != -1) return dp[x][y] ; 
if (graph[x][y] == '#') 
return dp[x][y] = 0 ; 

if (x+1 <= n) ans += dfs (x+1, y) ; 
if (y+1 <= n) ans += dfs (x, y+1) ; 
return dp[x][y] = ans%MOD ; 
}


int main () 
{
int i, j ; 
while (~scanf ("%d", &n)) 
{
REP(i,1,n) scanf ("%s", &graph[i][1]) ; 
if (graph[1][1] == '#'){ 
puts ("INCONCEIVABLE") ; 
continue ; 
}
memset (dp, -1, sizeof(dp)) ; 
dp[n][n] = 1 ; 
dfs (1,1) ; 
bfs () ;
if (dp[1][1] != 0) printf ("%lld\n", dp[1][1]) ; 
else if (vis[n][n] != 0) printf ("THE GAME IS A LIE\n") ; 
else printf ("INCONCEIVABLE\n") ; 
}
return 0 ; 
}