//ライブラリへのリンク
//https://drive.google.com/drive/folders/1QDp2j94gwNBUf6lF2M-FTs9NVAKFpw5R

#include <bits/stdc++.h>
using namespace std;
using pii=pair<int,int>;
using tii=tuple<int,int,int>;
using qii=tuple<int,int,int,int>;
using ll=long long;
using ull=unsigned long long;
using ld=long double;
constexpr int INF=1e9;
constexpr ll INF_ll=1e18;
#define rep(i,n) for (int i=0;i<(int)(n);i++)
#define replr(i,l,r) for (int i=(int)(l);i<(int)(r);i++)
#define all(v) v.begin(),v.end()
#define len(v) ((int)v.size())
template<class T> inline bool chmin(T &a,T b){
    if(a>b){
        a=b;
        return true;
    }
    return false;
}
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_ref(T &a,const T &b){
    if(a>b){
        a=b;
        return true;
    }
    return false;
}
template<class T> inline bool chmax_ref(T &a,const T &b){
    if(a<b){
        a=b;
        return true;
    }
    return false;
}

namespace Timer{
    chrono::steady_clock::time_point program_start,start;
    void program_start_snap(){
        program_start=start=chrono::steady_clock::now();
    }
    void snap(){
        start=chrono::steady_clock::now();
    }
    int get_ms(){
        auto now=chrono::steady_clock::now();
        int ms=chrono::duration_cast<chrono::milliseconds>(now-start).count();
        return ms;
    }
    int get_ms_all_program(){
        auto now=chrono::steady_clock::now();
        int ms=chrono::duration_cast<chrono::milliseconds>(now-program_start).count();
        return ms;
    }
}

mt19937 mt;
uint32_t rand_int(uint32_t r){  //[0,r)
    assert(r!=0);
    return ((uint64_t)mt()*r)>>32;
}
int rand_int(int l,int r){  //[l,r)
    assert(l<r);
    return l+rand_int(r-l);
}
constexpr double one_div_mt_max=1.0/(double)mt19937::max();
double rand_double(){  //[0.0,1.0]
    return mt()*one_div_mt_max;
}
double rand_double(double l,double r){  //[l,r]
    return l+rand_double()*(r-l);
}
template<class T> T get_random_element(const vector<T> &v){
    assert(!v.empty());
    return v[rand_int(len(v))];
}

template<class T> void add(vector<T> &a,vector<T> b){
    for(auto i:b) a.push_back(i);
}

constexpr int N=50,K=100;

array<int,N*N> D;
array<array<int,4>,N*N> G;

int one(int i,int j){
    return i*N+j;
}
pii two(int x){
    return {x/N,x%N};
}

namespace Solver{
    
    double calc_e(const array<bool,N*N> &is_cut){
        
        array<bool,N*N> is_tree;
        
        is_tree.fill(false);
        
        rep(i,N*N){
            if(is_cut[i]) continue;
            if((int)rand_int(10)<D[i]) is_tree[i]=true;
        }
        
        array<int,N*N> root;
        
        root.fill(-1);
        
        rep(i,N*N){
            if(!is_tree[i]) continue;
            if(root[i]!=-1) continue;
            
            queue<int> q;
            
            q.push(i);
            
            root[i]=i;
            
            while(!q.empty()){
                int x=q.front();
                q.pop();
                for(auto y:G[x]){
                    if(!is_tree[y]) continue;
                    if(root[y]!=-1) continue;
                    root[y]=i;
                    q.push(y);
                }
            }
            
        }
        
        array<int,N*N> cnt;
        cnt.fill(0);
        
        
        rep(i,N*N){
            if(root[i]!=-1) cnt[root[i]]++;
        }
        
        
        double ret=0;
        
        rep(i,N*N){
            ret+=cnt[i]*cnt[i];
        }
        
        ret/=N*N;
        
        return ret;
        
    }
    
    double e0=0;
    
    double calc_score(const array<bool,N*N> &is_cut,int try_turn){
        assert(try_turn!=0);
        double e=0;
        rep(_,try_turn) e+=calc_e(is_cut);
        e/=try_turn;
        return 1e6*(1+log(e0/e));
    }
    
    void solve(){
        
        array<bool,N*N> is_cut,best_is_cut;
        
        is_cut.fill(false);
        best_is_cut.fill(false);
        
        rep(_,1000) e0+=calc_e(is_cut);
        e0/=1000;
        
        
        
        
        /*double best_score=0;
        
        rep(i,N*N){
            
            auto new_is_cut=is_cut;
            
            new_is_cut[i]=true;
            
            double new_score=calc_score(new_is_cut,100);
            
            cerr << i << " " << new_score << " " << best_score << endl;
            
            if(best_score<new_score){
                best_score=new_score;
                best_is_cut=new_is_cut;
            }
        }*/
        
        rep(i,N){
            best_is_cut[one(i,N/2)]=true;
            best_is_cut[one(N/2,i)]=true;
        }
        
        vector<int> ans;
        
        rep(i,N*N){
            if(D[i]==0) continue;
            if(best_is_cut[i]) ans.push_back(i);
        }
        
        assert(len(ans)<K);
        
        cout << len(ans) << '\n';
        
        for(auto p:ans){
            auto [i,j]=two(p);
            cout << i << ' ' << j << '\n';
        }
    }
}

int main(){
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    Timer::program_start_snap();
    
    int n,k;
    cin >> n >> k;
    
    
    rep(i,N){
        rep(j,N){
            char c;
            cin >> c;
            D[one(i,j)]=c-'0';
        }
    }
    
    rep(i,N*N) G[i].fill(-1);
    
    rep(i,N){
        rep(j,N){
            if(j+1<N){
                G[one(i,j)][3]=one(i,j+1);
                G[one(i,j+1)][2]=one(i,j);
            }
            if(i+1<N){
                G[one(i,j)][1]=one(i+1,j);
                G[one(i+1,j)][0]=one(i,j);
            }
        }
    }



    Solver::solve();
    exit(0);
}