#include <bits/stdc++.h>

using namespace std;
int n;
int main()
{
    srand(time(NULL));
    cin>>n;
    freopen(".20.in","w",stdout);
    cout<<n<<endl;
    while( n-- )
    {
        long long x, y;
        x = rand()%100;
        y = rand()%100;
        if( rand()%2 ) x *= -1;
        if( rand()%2 ) y *= -1;
        if( x > y ) swap(x, y);
        cout<<x<<" "<<y<<endl;
    }
}