#include <bits/stdc++.h>
using namespace std;
#define int long long
#define FOR(i, s, n) for (int i = (s); i < (int)(n); i++)
#define RFOR(i, s, n) for (int i = (n) - 1; i >= (int)(s); i--)
#define REP(i, n) FOR(i, 0, n)
#define RREP(i, n) RFOR(i, 0, n)
#define ALL(a) a.begin(), a.end()
constexpr long long INF = 1e18;
template<class T>inline bool CHMAX(T&a,T b){if(a<b){a=b;return true;}return false;}
template<class T>inline bool CHMIN(T&a,T b){if(a>b){a=b;return true;}return false;}



signed main(){
	int N,K;
	cin >> N >> K;
	int gridSize = (N+K-1)/K;
	vector<vector<char>>a(gridSize,vector<char>(gridSize,'.'));
	int cnt = N;
	for(int i = 0;i < gridSize;){
		for(int j = 0;j < gridSize;){
			REP(k,K){
				REP(l,K){
					if(cnt == 0)break;
					a[i+k][j+l] = '#';
					cnt--;
				}
			}
			i += K;
			j += K;
		}
	}
	cout << gridSize << endl;
	REP(i,gridSize){
		REP(j,gridSize){
			if(j)cout << " ";
			cout << a[i][j];
		}
		cout << endl;
	}
}