#include <bits/stdc++.h>
using namespace std;
#define rep(i,a,n) for (int i=a;i<n;i++)
#define per(i,a,n) for (int i=n-1;i>=a;i--)
#define pb push_back
#define eb emplace_back
#define mp make_pair
#define all(x) (x).begin(),(x).end()
#define fi first
#define se second
#define SZ(x) ((int)(x).size())
typedef vector<int> VI;
typedef basic_string<int> BI;
typedef long long ll;
typedef pair<int,int> PII;
typedef double db;
mt19937 mrand(random_device{}()); 
const ll mod=1000000007;
int rnd(int x) { return mrand() % x;}
ll powmod(ll a,ll b) {ll res=1;a%=mod; assert(b>=0); for(;b;b>>=1){if(b&1)res=res*a%mod;a=a*a%mod;}return res;}
ll gcd(ll a,ll b) { return b?gcd(b,a%b):a;}
// head

const int N=101000;
char s[N];
int n;
int b[N],v[N];
map<int,int> hs;
vector<PII> ret;
void add(int x,int y) {
	// x->y
	ret.pb(mp(-x,y));
}
int main() {
	scanf("%d",&n);
	rep(i,0,3) {
		scanf("%s",s);
		rep(j,1,n+1) b[j]=b[j]*2+(s[j-1]-'0');
	}
	rep(i,1,n+1) {
		v[i]=i;
		if (b[i]>=4) v[i]=-i,b[i]=7-b[i];;
		if (b[i]==0) add(v[i],-v[i]);
		else if (hs.count(b[i])) {
			add(hs[b[i]],v[i]);
			add(-hs[b[i]],-v[i]);
		} else {
			hs[b[i]]=v[i];
		}
	}
	assert(SZ(hs)>=2&&SZ(hs)<=3);
	int p001=hs[1],p010=hs[2],p011=hs[3];
	if (p011==0) {
		add(p001,-p010);
	} else if (p001==0) {
		add(p010,p011);
	} else if (p010==0) {
		add(p001,p011);
	} else {
		add(p001,-p010);
		add(p001,p011);
		add(p010,p011);
		//fprintf(stderr,"4\n");
	}
	printf("%d\n",SZ(ret));
	for (auto [x,y]:ret) printf("%d %d\n",x,y);
}