#pragma GCC optimize(2,3,"Ofast","Ofast,no-stack-protector,unroll-loops")
#define debug(x) cerr<<(#x)<<" "<<x<<"\n"
#include<bits/stdc++.h>
typedef int ll;
typedef long double ld;
typedef unsigned long long ull;
#define pii pair<ll,ll>
#define rep(i,a,b) for(ll i=(a);i<=(b);++i)
#define per(i,a,b) for(ll i=(a);i>=(b);--i)
using namespace std;
bool Mbe;
ll read(){
	ll x=0,f=1;char ch=getchar();
	while(ch<'0'||ch>'9'){if(ch=='-')f=-1;ch=getchar();}
	while(ch>='0'&&ch<='9'){x=(x<<3)+(x<<1)+(ch^'0');ch=getchar();}
	return x*f;
}
void write(ll x){
	if(x<0)putchar('-'),x=-x;
	if(x>9)write(x/10);
	putchar(x%10+'0');
}
const ll N=2059;
ll n,a[N][N],cur=1,rd;
bitset<N>b[2][N];
bool Med;
int main(){
	cerr<<fabs(&Med-&Mbe)/1048576.0<<"MB\n";
	rd=read(),n=(1<<rd);
	rep(i,0,n-1){
		rep(j,0,n-1)a[i][j]=read();
	}
	rep(i,0,n-1){
		rep(j,0,n-1)b[0][i][j]=a[i][j];
	}
	rd--;
	while(rd--){
		rep(i,0,n){
			rep(j,0,n)b[cur][i][j]=0;
		}
		rep(i,0,n-1){
			rep(j,0,n-1){
				if(b[cur^1][i][j]){
					b[cur][i].flip(j);
					b[cur][(i+(1<<rd))%n].flip(j);
					b[cur][((i-(1<<rd))%n+n)%n].flip(j);
					b[cur][i].flip((j+(1<<rd))%n);
					b[cur][i].flip(((j-(1<<rd))%n+n)%n);
				}
			}
		}
		cur^=1;
	}
	ll cnt=0;
	rep(i,0,n-1){
		rep(j,0,n-1)cnt+=b[cur^1][i][j];
	}
	write(cnt),putchar('\n');
	rep(i,0,n-1){
		rep(j,0,n-1){
			if(b[cur^1][i][j])write(i),putchar(' '),write(j),putchar('\n');
		}
	}
	return 0;
}