#include<bits/stdc++.h>
using namespace std;


const int N = 1005, INF = 1e9 + 1337;
const int dx[] = {-1, 0, 1, 0},
          dy[] = {0, -1, 0, 1};


int n, m, maxL, a[N][N];
bool used[N][N];
int p[N][N], cl;
vector < pair < int, int > > q[N * N];

inline bool check(int x, int y){
    return 1 <= x && x <= n && 1 <= y && y <= m;
}
void dfsFind(int x, int y){
    p[x][y] = cl;
    for(int i = 0; i < 4; i++){
        int xx = x + dx[i],
            yy = y + dy[i];
        if(check(xx, yy) && !p[xx][yy] && a[xx][yy] != -1){
            dfsFind(xx, yy);
        }
    }
}

mt19937 rnd(time(nullptr));

long long ans = -1;
vector < pair < int, int > > ans_path, cur_path;

inline int LIS(vector < int > &q){
    int n = (int)q.size();
    vector < int > dp(n + 1, INF);
    dp[0] = -1;
    for(int i = 0; i < (int)q.size(); i++){
        int x = q[i];
        int j = upper_bound(dp.begin(), dp.end(), x) - dp.begin();
        if(dp[j - 1] < x && x < dp[j]){
            dp[j] = x;
        }
    }
    for(int i = n; i >= 0; i--){
        if(dp[i] != INF){
            return i;
        }
    }
}

inline int LDS(vector < int > &q){
    int n = (int)q.size();
    vector < int > dp(n + 1, INF);
    dp[0] = -1;
    for(int i = (int)q.size() - 1; i >= 0; i--){
        int x = q[i];
        int j = upper_bound(dp.begin(), dp.end(), x) - dp.begin();
        if(dp[j - 1] < x && x < dp[j]){
            dp[j] = x;
        }
    }
    for(int i = n; i >= 0; i--){
        if(dp[i] != INF){
            return i;
        }
    }
}

inline long long path_value(vector < pair < int, int > > &q){
    vector < int > vals;
    for(auto it : q){
        if(a[it.first][it.second] == -1){
            return -2;
        }
        vals.push_back(a[it.first][it.second]);
    }
    return 1LL * LIS(vals) * LDS(vals);
}

/// ch1 priority OK
void dfs1(int x, int y){
    if((int)cur_path.size() == maxL){
        long long res = path_value(cur_path);
        if(res > ans){
            ans = res;
            ans_path = cur_path;
        }
        return;
    }
    vector < pair < int, int > > ch1, ch2;
    for(int i = 0; i < 4; i++){
        int xx = x + dx[i],
            yy = y + dy[i];
        if(check(xx, yy) && p[xx][yy] == p[x][y] && !used[xx][yy]){
            if(a[xx][yy] != a[x][y]){
                ch1.push_back(make_pair(xx, yy));
            }
            else{
                ch2.push_back(make_pair(xx, yy));
            }
        }
    }
    if(ch1.empty() && ch2.empty()){
        long long res = path_value(cur_path);
        if(res > ans){
            ans = res;
            ans_path = cur_path;
        }
        return;
    }
    if(ch1.empty()){
        int pos = rnd() % (int)ch2.size();
        int xx = ch2[pos].first,
            yy = ch2[pos].second;
        used[xx][yy] = true;
        cur_path.push_back(make_pair(xx, yy));
        dfs1(xx, yy);
        cur_path.pop_back();
        used[xx][yy] = false;
    }
    else{
        int pos = rnd() % (int)ch1.size();
        int xx = ch1[pos].first,
            yy = ch1[pos].second;
        used[xx][yy] = true;
        cur_path.push_back(make_pair(xx, yy));
        dfs1(xx, yy);
        cur_path.pop_back();
        used[xx][yy] = false;
    }
}
/// ch2 priority OK
void dfs2(int x, int y){
    if((int)cur_path.size() == maxL){
        long long res = path_value(cur_path);
        if(res > ans){
            ans = res;
            ans_path = cur_path;
        }
        return;
    }
    vector < pair < int, int > > ch1, ch2;
    for(int i = 0; i < 4; i++){
        int xx = x + dx[i],
            yy = y + dy[i];
        if(check(xx, yy) && p[xx][yy] == p[x][y] && !used[xx][yy]){
            if(a[xx][yy] != a[x][y]){
                ch1.push_back(make_pair(xx, yy));
            }
            else{
                ch2.push_back(make_pair(xx, yy));
            }
        }
    }
    if(ch1.empty() && ch2.empty()){
        long long res = path_value(cur_path);
        if(res > ans){
            ans = res;
            ans_path = cur_path;
        }
        return;
    }
    if(ch2.empty()){
        int pos = rnd() % (int)ch1.size();
        int xx = ch1[pos].first,
            yy = ch1[pos].second;
        used[xx][yy] = true;
        cur_path.push_back(make_pair(xx, yy));
        dfs2(xx, yy);
        cur_path.pop_back();
        used[xx][yy] = false;
    }
    else{
        int pos = rnd() % (int)ch2.size();
        int xx = ch2[pos].first,
            yy = ch2[pos].second;
        used[xx][yy] = true;
        cur_path.push_back(make_pair(xx, yy));
        dfs2(xx, yy);
        cur_path.pop_back();
        used[xx][yy] = false;
    }
}
/// random 0/1 priority OK
void dfs3(int x, int y){
    if((int)cur_path.size() == maxL){
        long long res = path_value(cur_path);
        if(res > ans){
            ans = res;
            ans_path = cur_path;
        }
        return;
    }
    vector < pair < int, int > > ch1, ch2;
    for(int i = 0; i < 4; i++){
        int xx = x + dx[i],
            yy = y + dy[i];
        if(check(xx, yy) && p[xx][yy] == p[x][y] && !used[xx][yy]){
            if(a[xx][yy] != a[x][y]){
                ch1.push_back(make_pair(xx, yy));
            }
            else{
                ch2.push_back(make_pair(xx, yy));
            }
        }
    }
    if(ch1.empty() && ch2.empty()){
        long long res = path_value(cur_path);
        if(res > ans){
            ans = res;
            ans_path = cur_path;
        }
        return;
    }
    if(ch2.empty()){
        int pos = rnd() % (int)ch1.size();
        int xx = ch1[pos].first,
            yy = ch1[pos].second;
        used[xx][yy] = true;
        cur_path.push_back(make_pair(xx, yy));
        dfs3(xx, yy);
        cur_path.pop_back();
        used[xx][yy] = false;
    }
    else if(ch1.empty()){
        int pos = rnd() % (int)ch2.size();
        int xx = ch2[pos].first,
            yy = ch2[pos].second;
        used[xx][yy] = true;
        cur_path.push_back(make_pair(xx, yy));
        dfs3(xx, yy);
        cur_path.pop_back();
        used[xx][yy] = false;
    }
    else if(rnd() & 1){
        int pos = rnd() % (int)ch1.size();
        int xx = ch1[pos].first,
            yy = ch1[pos].second;
        used[xx][yy] = true;
        cur_path.push_back(make_pair(xx, yy));
        dfs3(xx, yy);
        cur_path.pop_back();
        used[xx][yy] = false;
    }
    else{
        int pos = rnd() % (int)ch2.size();
        int xx = ch2[pos].first,
            yy = ch2[pos].second;
        used[xx][yy] = true;
        cur_path.push_back(make_pair(xx, yy));
        dfs3(xx, yy);
        cur_path.pop_back();
        used[xx][yy] = false;
    }
}
/// greedy OK
void dfs4(int x, int y){
    if((int)cur_path.size() == maxL){
        long long res = path_value(cur_path);
        if(res > ans){
            ans = res;
            ans_path = cur_path;
        }
        return;
    }
    vector < pair < int, int > > ch1, ch2;
    for(int i = 0; i < 4; i++){
        int xx = x + dx[i],
            yy = y + dy[i];
        if(check(xx, yy) && p[xx][yy] == p[x][y] && !used[xx][yy]){
            if(a[xx][yy] != a[x][y]){
                ch1.push_back(make_pair(xx, yy));
            }
            else{
                ch2.push_back(make_pair(xx, yy));
            }
        }
    }
    if(ch1.empty() && ch2.empty()){
        long long res = path_value(cur_path);
        if(res > ans){
            ans = res;
            ans_path = cur_path;
        }
        return;
    }
    random_shuffle(ch1.begin(), ch1.end());
    long long mx = -1;
    int xx, yy;
    for(auto it : ch1){
        cur_path.push_back(it);
        long long res = path_value(cur_path);
        if(res > mx){
            mx = res;
            xx = it.first;
            yy = it.second;
        }
        cur_path.pop_back();
    }
    random_shuffle(ch2.begin(), ch2.end());
    for(auto it : ch2){
        cur_path.push_back(it);
        long long res = path_value(cur_path);
        if(res > mx){
            mx = res;
            xx = it.first;
            yy = it.second;
        }
        cur_path.pop_back();
    }
    cur_path.push_back(make_pair(xx, yy));
    used[xx][yy] = true;
    dfs4(xx, yy);
    used[xx][yy] = false;
    cur_path.pop_back();
}

/**
3 3
1 3 -1
-1 2 1
-1 1 1
4

1 5
4 3 -1 2 3
4
*/

int main(){
    srand(time(nullptr));
    ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
    freopen("path.in", "r", stdin);freopen("path.out", "w", stdout);
    clock_t begin_t = clock();
    cin >> n >> m;
    for(int i = 1; i <= n; i++){
        for(int j = 1; j <= m; j++){
            cin >> a[i][j];
        }
    }
    cin >> maxL;
    for(int i = 1; i <= n; i++){
        for(int j = 1; j <= m; j++){
            if(!p[i][j] && a[i][j] != -1){
                cl++;
                dfsFind(i, j);
            }
        }
    }
    for(int i = 1; i <= n; i++){
        for(int j = 1; j <= m; j++){
            if(a[i][j] != -1){
                q[p[i][j]].push_back(make_pair(i, j));
            }
        }
    }
    if(n == 1){
        for(int i = 1; i <= m; i++){
            for(int j = i; j <= min(i + maxL - 1, m); j++){
                cur_path.push_back(make_pair(1, j));
            }
            long long res = path_value(cur_path);
            if(res > ans){
                ans = res;
                ans_path = cur_path;
            }
            cur_path.clear();
        }
        for(int i = m; i >= 1; i--){
            for(int j = i; j >= max(i - maxL + 1, 1); j--){
                cur_path.push_back(make_pair(1, j));
            }
            long long res = path_value(cur_path);
            if(res > ans){
                ans = res;
                ans_path = cur_path;
            }
            cur_path.clear();
        }
    }
    if(m == 1){
        for(int i = 1; i <= n; i++){
            for(int j = i; j <= min(i + maxL - 1, n); j++){
                cur_path.push_back(make_pair(j, 1));
            }
            long long res = path_value(cur_path);
            if(res > ans){
                ans = res;
                ans_path = cur_path;
            }
            cur_path.clear();
        }
        for(int i = n; i >= 1; i--){
            for(int j = i; j >= max(i - maxL + 1, 1); j--){
                cur_path.push_back(make_pair(j, 1));
            }
            long long res = path_value(cur_path);
            if(res > ans){
                ans = res;
                ans_path = cur_path;
            }
            cur_path.clear();
        }
    }
    if(n <= 100 && m <= 100){
        do{
            for(int i = 1; i <= cl; i++){
                int pos = rnd() % (int)q[i].size();
                int x = q[i][pos].first,
                    y = q[i][pos].second;
                cur_path.push_back(make_pair(x, y));
                used[x][y] = true;
                dfs1(x, y);
                used[x][y] = false;
                cur_path.pop_back();
            }
        }while(clock() - begin_t <= 1.0 * CLOCKS_PER_SEC);
        do{
            for(int i = 1; i <= cl; i++){
                int pos = rnd() % (int)q[i].size();
                int x = q[i][pos].first,
                    y = q[i][pos].second;
                cur_path.push_back(make_pair(x, y));
                used[x][y] = true;
                dfs2(x, y);
                used[x][y] = false;
                cur_path.pop_back();
            }
        }while(clock() - begin_t <= 2.0 * CLOCKS_PER_SEC);
        do{
            for(int i = 1; i <= cl; i++){
                int pos = rnd() % (int)q[i].size();
                int x = q[i][pos].first,
                    y = q[i][pos].second;
                cur_path.push_back(make_pair(x, y));
                used[x][y] = true;
                dfs3(x, y);
                used[x][y] = false;
                cur_path.pop_back();
            }
        }while(clock() - begin_t <= 3.0 * CLOCKS_PER_SEC);
        do{
            for(int i = 1; i <= cl; i++){
                int pos = rnd() % (int)q[i].size();
                int x = q[i][pos].first,
                    y = q[i][pos].second;
                cur_path.push_back(make_pair(x, y));
                used[x][y] = true;
                dfs3(x, y);
                used[x][y] = false;
                cur_path.pop_back();
            }
        }while(clock() - begin_t <= 4.8 * CLOCKS_PER_SEC);
        cout << (int)ans_path.size() << "\n";
        for(auto it : ans_path){
            cout << it.first << " " << it.second << "\n";
        }
    }
    else{
        do{
            for(int i = 1; i <= cl; i++){
                int pos = rnd() % (int)q[i].size();
                int x = q[i][pos].first,
                    y = q[i][pos].second;
                cur_path.push_back(make_pair(x, y));
                used[x][y] = true;
                dfs1(x, y);
                used[x][y] = false;
                cur_path.pop_back();
            }
        }while(clock() - begin_t <= 1.9 * CLOCKS_PER_SEC);
        do{
            for(int i = 1; i <= cl; i++){
                int pos = rnd() % (int)q[i].size();
                int x = q[i][pos].first,
                    y = q[i][pos].second;
                cur_path.push_back(make_pair(x, y));
                used[x][y] = true;
                dfs2(x, y);
                used[x][y] = false;
                cur_path.pop_back();
            }
        }while(clock() - begin_t <= 3.8 * CLOCKS_PER_SEC);
        do{
            for(int i = 1; i <= cl; i++){
                int pos = rnd() % (int)q[i].size();
                int x = q[i][pos].first,
                    y = q[i][pos].second;
                cur_path.push_back(make_pair(x, y));
                used[x][y] = true;
                dfs3(x, y);
                used[x][y] = false;
                cur_path.pop_back();
            }
        }while(clock() - begin_t <= 4.8 * CLOCKS_PER_SEC);
        cout << (int)ans_path.size() << "\n";
        for(auto it : ans_path){
            cout << it.first << " " << it.second << "\n";
        }
    }