#include<bits/stdc++.h>
using namespace std;
double h[1005];
int k[1005][1005];
int n,m;
int b[1000005][2];
int bi=0;
int main(){
	cin>>n>>m;
	for(int i=1;i<=n;i++){
		double a=0.0,ans=0.0;
		for(int j=1;j<=m;j++){
			cin>>k[i][j];
			a+=(double)k[i][j];
		}
		a/=(double)m;
		for(int j=1;j<=m;j++){
			ans+=(k[i][j]-a)*(k[i][j]-a);
		}
		h[i]+=ans/(double)m;
	}
	for(int i=1;i<=n;i++){
		double a=0.0,ans=0.0;
		for(int j=1;j<=m;j++){
			cin>>k[i][j];
			a+=(double)k[i][j];
		}
		a/=(double)m;
		for(int j=1;j<=m;j++){
			ans+=(k[i][j]-a)*(k[i][j]-a);
		}
		h[i]+=ans/(double)m;
	}
	for(int i=m;i>=1;i--){
		for(int j=2;j<=i;j++){
			if(h[j]<h[j-1]){
				swap(h[j],h[j-1]);
				bi++;
				b[bi][0]=j-1;
				b[bi][1]=j;
			}
		}
	}
	cout<<bi<<endl;
	for(int i=1;i<=bi;i++){
		cout<<b[i][0]<<" "<<b[i][1]<<endl;
	}
}