#include<bits/stdc++.h>
using namespace std;
#define ALL(x) x.begin(),x.end()
#define rep(i,n) for(int i=0;i<(n);i++)
#define debug(v) cout<<#v<<":";for(auto x:v){cout<<x<<' ';}cout<<endl;
#define INF 1000000000
#define mod 1000000007
using ll=long long;
const ll LINF=1001002003004005006ll;
int dx[]={1,0,-1,0};
int dy[]={0,1,0,-1};
ll gcd(ll a,ll b){return b?gcd(b,a%b):a;}
template<class T>bool chmax(T &a,const T &b){if(a<b){a=b;return true;}return false;}
template<class T>bool chmin(T &a,const T &b){if(b<a){a=b;return true;}return false;}



signed main(){
    cin.tie(0);
    ios::sync_with_stdio(0);

    ll n,k;cin>>n>>k;
    if(k*k>=n){
        for(int i=0;n;i++){
            for(int j=0;j<k;j++){
                if(n){
                    cout<<'#';
                    n--;
                }else{
                    cout<<'.';
                }
            }cout<<"\n";
        }
    }

    ll t=(n+k*k-1)/(k*k);//繰り返し回数
    bool ans[t*k][t*k]={};
    for(int l=0;l<t;l++){
        rep(i,k){
            rep(j,k){
                ans[l*k+i][l*k+j]=true;
            }
        }
    }

    ll ov=k*k*t-n;
    for(int i=0;i<k;i++){
        for(int j=0;j<k;j++){
            if(ov){
                ans[i][j]=false;
                ov--;
            }
        }
    }

    cout<<t*k<<endl;
    rep(i,t*k){
        rep(j,t*k){
            cout<<(ans[i][j]?'#':'.');
        }cout<<'\n';
    }
    return 0;
}