// #pragma GCC target("avx2")
#pragma GCC optimization ("O3")
#pragma GCC optimization ("unroll-loops")
#pragma GCC optimization ("Ofast")
//#pragma GCC -Wnarrowing

//Template {
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#include <chrono>
using namespace std;
using namespace __gnu_pbds;
 
//IO templates
//Note: use endl only for interactive problems or to debug segfaults; use newl for other problems
#define newl "\n"
#define fastIO ios::sync_with_stdio(false); cin.tie(nullptr)
#define fileIO(x) ifstream fin((str) x + (str) ".in"); ofstream fout((str) x + (str) ".out");
// void fileIO(string x) {}
#define flush() fflush(stdout)
#define interact(n) fflush(stdout); cin >> n; if (n == -1) return 0
#define testcases int tt; cin >> tt; fun (i, tt) solve();

#define edgeIO(m) fun (i, m) {int a, b; cin >> a >> b; addEdges(a, b);}
#define WeightedEdgeIO(m) fun (i, m) {int a, b, c; cin >> a >> b >> c; addWeightedEdges(a, b, c);}
#define numberedEdgeIO(m) fun (i, m) {int a, b; cin >> a >> b; addWeightedEdges(a, b, i);}
//types
#define ordered_set tree<int, null_type,less<int>, rb_tree_tag,tree_order_statistics_node_update>
#define ordered_multiset tree<int, null_type,less_equal<int>, rb_tree_tag,tree_order_statistics_node_update>
#define ll long long
#define int long long
#define ld long double
#define str string
#define boolean bool
#define String string
 
//vector
#define pb push_back
#define append push_back
 
//pairs
#define mp make_pair
#define p2 pair<int, int>
#define p3 pair<int, p2>
#define m3(x, y, z) mp(x, mp(y, z))
#define ich first
#define ni second.first
#define sanshi second.second
 
//For loops
#define ahegao(i, a, b) for (int i = a; i < b; i++)
#define baka(i, b, a) for (int i = b; i > a; i--)
#define fun(i, n) for (int i = 1; i <= (n); (i)++)
#define fon(i, n) for (int i = 0; i < (n); (i)++)
#define fur(i, n) for (auto i : (n))
#define oniichan(i, n) for (auto &i : (n))
 
//Sorts
#define sz(aaa) ((signed) aaa.size())
// #define len(aaa) ((signed) aaa.size())
#define all(a) a.begin(), a.end()
#define Sort(a) sort((a).begin(), (a).end())
#define rSort(a) sort((a).rbegin(), (a).rend())
#define clamp(x, y) (x) = min((int) (x), (int) (y))
#define CLAMP(x, y) (x) = max((int) (x), (int) (y))
 
//Other stuff
#define pqueue priority_queue
#define elif else if
#define addEdges(a, b) adj[a].pb(b); adj[b].pb(a)
#define addWeightedEdges(a, b, c) adj[a].pb(mp(b, c)); adj[b].pb(mp(a, c))
// #define find find_by_order
#define printLength(x) if (x < INF) cout << x << newl; else cout << -1 << newl;
// #define printVector(a) fur (i, a) cout << i << ' '; cout << newl;
void printVector(vector<int> DontUseThisName) {
    fur (i, DontUseThisName) cout << i << ' '; cout << newl;
}
void printVector(vector<p2> DontUseThisName) {
    fur (i, DontUseThisName) cout << i.first << ' ' << i.second << newl; cout << newl;
}
void printVector(vector<vector<int>> DontUseThisName) {
    fur (i, DontUseThisName) printVector(i); cout << newl;
}
ll max(ll a, signed b) {return max(a, (ll) b);}
ll max(signed a, ll b) {return max((ll) a, b);}

void pv(int a) {cout << a << newl;}
void pv(int a, int b) {printVector({a, b});}
void pv(p2 a) {printVector({a.first, a.second});};
void pv(int a, int b, int c) {printVector({a, b, c});}
void pv(int a, int b, int c, int d) {printVector({a, b, c, d});}
void pv(int a, int b, int c, int d, int e) {printVector({a, b, c, d, e});}
void pv(int a, int b, int c, int d, int e, int f) {printVector({a, b, c, d, e, f});}
// void pv(int a, )
// void printVector(vector<char> DontUseThisName) {
//     fur (i, DontUseThisName) cout << i << ' '; cout << newl;
// }
// void printRange(vector<int>::iterator Left, vector<int>::iterator Right) {
//     for (auto i = Left; i < Right; i++) cout << *i << ' ';
//     cout << newl;
// } 
//Constants
const int MOD =  1e9+7; // 998244353
// const int SMALLMOD = 998244353;
const int INF = 2e9+1337;
const ll EXCEED = 2e18+1337;
const ll GRAVITY = 8e18;

//#define vectorIO(n, MikuBondage) fun (j, n) {int i; cin >> i; MikuBondage.pb(i);}
void vectorIO(int n, vector<int> &DontUseThisName) {
    fun (j, n) {int i; cin >> i; DontUseThisName.pb(i);}
}
//#define vector2IO(n, MikuBondage) fun (j, n) {int i, ii; cin >> i >> ii; MikuBondage.pb(mp(i, ii));}
void vector2IO(int n, vector<p2> &DontUseThisName) {
    fun (j, n) {int i, ii; cin >> i >> ii; DontUseThisName.pb(mp(i, ii));}
}

// const int dx[4] = {1, -1, 0, 0}, dy[4] = {0, 0, 1, -1};
#define shortest_path_queue priority_queue<p2, vector<p2>, greater<p2>>
#define printArray(DontUseThisName, NakedLolisGalore, GenshinImpactClimbing) ahegao (j, NakedLolisGalore, GenshinImpactClimbing + 1) cout << DontUseThisName[j] << ' '; cout << newl;
#define print2dArray(SplitComplexProblemsIntoMultipleParts, ScuteSwarm, GenshinImpactClimbing) fun (i, ScuteSwarm) {fun (j, GenshinImpactClimbing) cout << SplitComplexProblemsIntoMultipleParts[i][j] << ' '; cout << newl;}
//}

#include <chrono>
unsigned rng = chrono::steady_clock::now().time_since_epoch().count();
int randint(int k) {
    rng = 1337 * (rng % 483187) + (rng << 5) + 987654321 + (rng % 235612) * (rng * 55679);
    return rng % k;
}

const int MAX = 2003;
int n, val[MAX][MAX], inv[MAX][MAX];
bool badRow[MAX], badCol[MAX];
int x[MAX], y[MAX], z[MAX];

bool checkRow(int i, int j) {
    int res = 0;
    fun (k, n) res = (res + inv[i][k] * val[k][j]) % MOD;
    
    int temp = i == j;
    pv(res, temp);
    if (res != temp) badRow[i] = true;
    return res == (i == j);
}

bool checkColumn(int i, int j) {
    int res = 0;
    fun (k, n) res = (res + val[i][k] * inv[k][j]) % MOD;
    // cout << res << newl;
    int temp = i == j;
    pv(res, temp);
    if (res != temp) badCol[j] = true;
    return res == (i == j);
}

int inverse(int a) {
    int b = MOD - 2;
    int res = 1;
    // int i = 0;
    baka(i, 30, -1) {
        res = (res * res) % MOD;
        if (b & (1 << i)) {
            // cout << i << newl;
            res = (res * a) % MOD;
        }
    }
    return res;
}

vector<int> solve(vector<vector<int>> &nums) {
    int k = sz(nums);
    fon (i, k) {
        int temp = inverse(nums[i][i]);
        ahegao (j, i, k+1) {
            nums[i][j] *= temp;
            nums[i][j] %= MOD;
        }
        // printVector(nums);
        ahegao (l, i+1, k) {
            int curr = nums[l][i];
            ahegao(j, i, k+1) {
                nums[l][j] += curr * (MOD - nums[i][j]);
                nums[l][j] %= MOD;
            }
        }
        // printVector(nums);
    }
    baka (i, k-1, -1) {
        baka (j, i-1, -1) {
            nums[j][k] += nums[j][i] * (MOD - nums[i][k]);
            nums[j][k] %= MOD;
            nums[j][i] = 0;
        }
        // printVector(nums);
    }
    vector<int> res;
    fon (i, k) res.pb(nums[i][k]);
    return res;
}

// bool checkColumn
signed main() {
    fastIO;
    cin >> n;
    fun (i, n) fun (j, n) cin >> val[i][j];
    fun (i, n) fun (j, n) cin >> inv[i][j];
    set<int> r, c;
    vector<int> rowPos, columnPos;
    fun (i, n) x[i] = randint(MOD);
    fun (i, n) fun(j, n) y[i] = y[i] + (val[i][j] * x[i]) % MOD;
    fun (i, n) fun(j, n) z[i] = z[i] + (inv[i][j] * y[i]) % MOD;
    fun (i, n) {
        if (x[i] != z[i]) {
            rowPos.pb(i);
            badRow[i] = true;
        }
    }
    // printArray(x, 1, n);
    // printArray(y, 1, n);
    // printArray(z, 1, n);
    fun (i, n) {
        x[i] = randint(MOD);
        y[i] = z[i] = 0;
    }
    fun (i, n) fun(j, n) y[i] = y[i] + (val[j][i] * x[i]) % MOD;
    fun (i, n) fun(j, n) z[i] = z[i] + (inv[j][i] * y[i]) % MOD;
    fun (i, n) {
        if (x[i] != z[i]) {
            columnPos.pb(i);
            badCol[i] = true;
        }
    }
    // printArray(x, 1, n);
    // printArray(y, 1, n);
    // printArray(z, 1, n);
    int pos = 1;
    // pv(sz(r), sz(c));
    // while (sz(r) < sz(c)) {
    //     r.insert(pos);
    //     pos++;
    // }
    // pos = 1;
    // while (sz(r) > sz(c)) {
    //     c.insert(pos);
    //     pos++;
    // }
    rowPos.insert(rowPos.end(), all(r));
    columnPos.insert(columnPos.end(), all(c));
    // printVector(rowPos);
    // printVector(columnPos);
    vector<vector<int>> MikuBondage;
    // fon (i, sz(rowPos)) fon (j, sz(columnPos)) {
        // pv(rowPos[i], columnPos[j]);
        // vector<int> temp(sz(rowPos) * sz(columnPos) + 1);
        // temp[sz(rowPos) * sz(columnPos)] = (rowPos[i] == columnPos[j]);
        // fon (k, sz(rowPos)) {
        //     temp[i * sz(rowPos) + k] = val[rowPos[k]][columnPos[j]];
        // }
        // MikuBondage.pb(temp);
        // printVector(temp);
    // }
    map<p2, int> badMap;
    pos = 0;
    fur (i, rowPos) fur (j, columnPos) {
        badMap[mp(i, j)] = pos;
        pos++;
    }
    fun (i, n) fun (j, n) {
        if (badRow[i] and badCol[j]) {
            vector<int> temp(sz(badMap)+1);
            temp[sz(badMap)] = (i == j);
            fun (k, n) {
                if (badRow[k]) temp[badMap[mp(k, j)]] = val[i][k];
                else temp[sz(badMap)] = (temp[sz(badMap)] + val[i][k] * (MOD - inv[k][j])) % MOD;
            }
            // pv(i, j);
            // printVector(temp);
            MikuBondage.pb(temp);
        }
    }
    // printVector(MikuBondage);
    vector<int> s = solve(MikuBondage);
    vector<vector<int>> MikuLewds;
    int out = 0;
    fun (i, n) fun (j, n) if (badRow[i] and badCol[j]) {
        int k = badMap[mp(i, j)];
        // pv(i, j, s[k]);
        if (s[k] != inv[i][j])
        MikuLewds.pb({i, j, s[k]});
    }
    
    Sort(MikuLewds);
    cout << sz(MikuLewds) << newl;
    printVector(MikuLewds);
}