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

#define x first
#define y second
// #define int long long
#define mp(x, y) make_pair(x, y)
#define eb(...) emplace_back(__VA_ARGS__)
#define fro(i, x, y) for(int i = (x); i <= (y); i++)
#define pre(i, x, y) for(int i = (x); i >= (y); i--)
inline void JYFILE19();

typedef int64_t i64;
typedef pair<int, int> PII;

bool ST;
const int N = (1<<11) + 8;
const int mod = 998244353;

int n, m;

struct MyBit {
	bitset<N> a;
	inline MyBit zuo() { auto b = (a<<1); b[1] = a[n], b[n + 1] = 0; return {b}; }
	inline MyBit you() { auto b = (a>>1); b[n] = a[1], b[1 - 1] = 0; return {b}; }
	inline void operator^=(const MyBit &tmp) { a ^= tmp.a; }
} d[2][N];

signed main() {
	JYFILE19();
	cin >> n, n = 1<<n, m = n-1;
	fro(i, 1, n) {
		fro(j, 1, n) {
			int x; cin >> x;
			d[0][i].a[j] = x;
		}
	}
	fro(i, 1, m) {
		int op = i & 1, las = op ^ 1;
		fro(j, 1, n) d[op][j] = d[las][j];
		fro(j, 1, n) d[op][j] ^= d[las][j].zuo();
		fro(j, 1, n) d[op][j] ^= d[las][j].you();
		fro(j, 1, n) d[op][j] ^= d[las][j - 1 == 0 ? n : j - 1];
		fro(j, 1, n) d[op][j] ^= d[las][j + 1 <= n ? j + 1 : 1];
	}
	int op = m & 1, ans = 0;
	fro(i, 1, n) {
		fro(j, 1, n) {
			if(d[op][i].a[j]) ans++;
		}
	}
	cout << ans << "\n";
	fro(i, 1, n) {
		fro(j, 1, n) {
			if(d[op][i].a[j]) cout << i - 1 << " " << j - 1<< "\n";
		}
	}
	return 0;
}

bool ED;
inline void JYFILE19() {
	// freopen("", "r", stdin);
	// freopen("", "w", stdout);
	ios::sync_with_stdio(0), cin.tie(0);
	double MIB = fabs((&ED-&ST)/1048576.), LIM = 32;
	cerr << "MEMORY: " << MIB << endl, assert(MIB<=LIM);
}