Printing Pattern using Loop

#include< stdio.h > int main() { int n; scanf( "%d" ,&n); int m= 2 *n- 1 ; int start= 0 ; int end=m- 1 ; int a[ 1000 ][ 1000 ]; while (n!= 0 ){ for ( int i=start;i<=end;i++){ for ( int j=start;j<=end;j++){ if (i==start ||i==end ||j==start|| j==end) a[i][j]=n; } } start++; end--; n--; } start= 0 ; end=m- 1 ; for ( int i= 0 ;i<=end;i++){ for ( int j= 0 ;j<=end;j++){ printf( "%d " ,a[i][j]); } printf( "\n" ); } return - 1 ; }