#include <bits/stdc++.h>
using namespace std;
namespace IO{
	const int sz=1<<22;
	char a[sz+5],b[sz+5],*p1=a,*p2=a,*t=b,p[205];
	#define gc() (p1==p2?(p2=(p1=a)+fread(a,1,sz,stdin),p1==p2?EOF:*p1++):*p1++)
	#define flush() (fwrite(b,1,t-b,stdout),t=b)
	#define pc(x) (*t++=x,(t-b==sz)?flush():nullptr)
//	#define gc() (getchar())
//	#define flush() (1)
//	#define pc(x) (putchar(x))
	template<class T> inline void read(T &x){
		x=0; char c=gc(),fushu=0;
		while(!isdigit(c)){if(c=='-')fushu=1; c=gc();}
		while(isdigit(c))x=x*10+(c^48),c=gc();
		if(fushu) x=-x;
	}
	inline void read(char &x){
		x=gc();
		while(!isgraph(x))x=gc();
	}
	inline void read(char *x){
		char c=gc();
		while(!isgraph(c))c=gc();
		while(isgraph(c))*x++=c,c=gc();
		*x='\0';
	}
	inline void read(string &x){
		x=""; char c=gc();
		while(!isgraph(c))c=gc();
		while(isgraph(c))x.push_back(c),c=gc();
	}
	template <typename T,typename ...Args> inline void read(T &x,Args &...args) { read(x),read(args...); }
	template<class T> inline void write(T x){
		if(x<0)pc('-'),x=-x;
		if(!x)pc('0');
		int l=0;
		while(x)p[++l]=(x%10)^48,x/=10;
		while(l)pc(p[l--]);
	}
	inline void write(char &x){pc(x);}
	inline void write(const char &x){pc(x);}
	inline void write(char *x){while(*x!='\0')pc(*x++);}
	inline void write(const char *x){while(*x!='\0')pc(*x++);}
	inline void write(string &x){for(auto c:x)pc(c);}
	template <typename T,typename ...Args> inline void write(T x,Args ...args) { write(x),write(args...); }
	struct F{~F(){flush();}}f;
	#undef gc
	#undef flush
	#undef pc
};
using IO::read;
using IO::write;
#define IOS ios::sync_with_stdio(0); cin.tie(0)
#define frein(name) freopen(name".in","r",stdin)
#define freout(name) freopen(name".out","w",stdout)
#define usefile(name) frein(name),freout(name)
#define fo(i,l,r) for(int i=(l);i<=(r);++i)
#define fu(i,l,r) for(int i=(l);i<(r);++i)
#define fd(i,r,l) for(int i=(r);i>=(l);--i)
#define ll long long
#define ull unsigned long long
#define ld long double
#define it128 __int128
#define pi pair<int,int>
#define pl pair<ll,ll>
#define fi first
#define se second
#define pb push_back
#define vi vector<int>
#define vp vector<pi>
#define mts multiset
#define udm unordered_map
#define prq priority_queue
#define endpos(x) prev(x.end())
#define Front(x) (*x.begin())
#define Back(x) (*endpos(x))
#define Size(x) ((int)x.size())
const int N=4096;
int n,m,a[N][N];
int f[2][N][N];
#define d(x) ((x)&1)
#define e(x) (d(x)^1)
int c(int x) {
	if(x<0) return x+m;
	if(x>=m) return x-m;
	return x;
}
#define w(x) (1<<(x))
signed main(){
	read(n); m=1<<n;
	fu(i,0,m) fu(j,0,m) read(a[i][j]);
	fu(i,0,m) fu(j,0,m) f[d(n-1)][i][j]=a[i][j];
	fd(p,n-1,1) {
		fu(i,0,m) fu(j,0,m) if(f[d(p)][i][j]) {
			f[d(p)][i][j]=0;
			f[e(p)][i][j]^=1;
			f[e(p)][c(i-w(p-1))][j]^=1;
			f[e(p)][i][c(j-w(p-1))]^=1;
			f[e(p)][c(i+w(p-1))][j]^=1;
			f[e(p)][i][c(j+w(p-1))]^=1;
		} 
	} 
	vp ans;
	fu(i,0,m) fu(j,0,m) if(f[0][i][j]) ans.pb({i,j});
	write(Size(ans),'\n');
	for(auto [x,y]:ans) write(x,' ',y,'\n');
	return 0;
}