#include <iostream>

using namespace std;

int n, k;
int ans[1005][1005];

int main(void)
{
	ios::sync_with_stdio(0);
	cin.tie(0);
	
	cin >> n >> k;
	int m = (n+k-1)/k;
	
	int rem = n, x = 0, y = 0;
	while(1){
		for(int i = 0; i < k; i++){
			for(int j = 0; j < k; j++){
				if(rem == 0) goto end;
				ans[x+i][y+j] = 1;
				rem--;
			}
		}
		x += k, y += k;
	}
	end:;
	
	cout << m << endl;
	for(int i = 0; i < m; i++){
		for(int j = 0; j < m; j++){
			if(ans[i][j]) cout << "#";
			else cout << ".";
		}
		cout << endl;
	}
	return 0;
}