#include<bits/stdc++.h>
using namespace std;
int n;
string s[3];
int zan[210000][2],ztop=0;
int jsq[3][120000];
void add(int x,int y){
	ztop++;
	zan[ztop][0]=x;
	zan[ztop][1]=y;
}
void sol(int x){
	for(int i=2;i<=jsq[x][0];i++){
		int pos1=jsq[x][1],pos2=jsq[x][i];
		if(s[0][pos1]==s[0][pos2]){
			add(-(pos1+1),(pos2+1));
			add((pos1+1),-(pos2+1));
		}
		else{
			add(-(pos1+1),-(pos2+1));
			add((pos1+1),(pos2+1));
		}
	}
}
int main(){
	cin>>n;
	cin>>s[0]>>s[1]>>s[2];
	for(int i=0;i<n;i++){
		if(s[0][i]==s[1][i]&&s[0][i]==s[2][i]){
			s[0][i]=='1'? add(i+1,i+1):add(-i-1,-i-1);
		}
		else if(s[1][i]==s[2][i]){
			jsq[0][++jsq[0][0]]=i;
		}
		else if(s[0][i]==s[2][i]){
			jsq[1][++jsq[1][0]]=i;
		}
		else if(s[0][i]==s[1][i]){
			jsq[2][++jsq[2][0]]=i;
		}
	}
	sol(0);sol(1);sol(2);
	int ab0=1,ab1=1,ab2=1;
	int pos0=jsq[0][1],pos1=jsq[1][1],pos2=jsq[2][1];
	if(jsq[0][0]&&s[0][pos0]=='1')ab0=-1;
	if(jsq[1][0]&&s[1][pos1]=='1')ab1=-1;
	if(jsq[2][0]&&s[2][pos2]=='1')ab2=-1;
	if(jsq[0][0]&&jsq[1][0]){
		add(ab0*(pos0+1),ab1*(pos1+1));
	}
	if(jsq[0][0]&&jsq[2][0]){
		add(ab0*(pos0+1),ab2*(pos2+1));
	}
	if(jsq[1][0]&&jsq[2][0]){
		add(ab1*(pos1+1),ab2*(pos2+1));
	}
	printf("%d\n",ztop);
	for(int i=1;i<=ztop;i++){
		printf("%d %d\n",zan[i][0],zan[i][1]);
	}
}