#include <bits/stdc++.h>
#define int long long
#define all(x) x.begin(),x.end()
#define ff first
#define ss second
#define pb push_back
using namespace std;
signed main(){
ios_base::sync_with_stdio(0);
cin.tie(0);cout.tie(0);
int n,m;
cin>>n>>m;
bool s=1;
vector <int> a(n),b(n);
for(int i=0;i<n;i++)cin>>a[i];
for(int i=0;i<n;i++){
cin>>b[i];
if(a[i]!=b[i])s=0;
}
if(m==1){
int res=1e9;
for(int i=0;i<n;i++){
res=min(res,max(a[i],b[i]));
}
cout<<res<<"\n";
}
else if(s){
int l=0,r=1e18;
while(l<=r){
int md=(l+r)/2;
int sum=0;
for(int i=0;i<n;i++){
sum+=(md+(a[i]-1))/a[i];
}
if(sum<=n*m)l=md+1;
else r=md-1;
}
cout<<r<<"\n";
}
else{
set <pair <int,int> > st;
vector <int> cnt(n);
for(int i=0;i<n;i++){
st.insert({max(a[i],b[i]),i});
if(a[i]>b[i])cnt[i]++;
}
for(int i=0;i<m*n-n;i++){
int x=st.begin()->ff;
int id=st.begin()->ss;
st.erase(st.begin());
if(a[id]>b[id] && cnt[id]<m){
x+=a[id];
cnt[id]++;
}
else x+=b[id];
st.insert({x,id});
}
cout<<st.begin()->ff<<"\n";
for(auto x : st){
cout<<x.ff<<" "<<x.ss<<'\n';
}
}
}
/*
4 25
1 2 3 4
1 2 3 4
12 6 3 4
3 3
19 4 5
2 6 2
5 60000
630510219 369411957 874325200 990002527 567203997
438920902 634940661 593780254 315929832 420627496
*/
