Function to store pascal triangle in 2 - d array
static void Preprocess ( ) { arr [ 0 , 0 ] = 1 ; for ( int i = 1 ; i <= 1000 ; ++ i ) { arr [ i , 0 ] = 1 ; for ( int j = 1 ; j < i ; ++ j ) { arr [ i , j ] = ( arr [ i - 1 , j - 1 ] + arr [ i - 1 , j ] ) % mod ; } arr [ i , i ] = 1 ; } }