#include <iostream>
#include <fstream>
#include <algorithm>
#include <cstring>

#define DN 104
using namespace std;

int v[DN*DN],n;
int rez[DN][DN];

ifstream f("test.in");
ofstream g("test.out");

void read(){


}

void solve(){

    cout<<97<<endl;
    cout<<1<<" ";
    for(int i=2;i<=100;i+=2)
        cout<<i<<" ";
    for(int i=2550;i<=2640;i+=2)
        cout<<i<<" ";
}

int main()
{
    read();
    solve();


    return 0;
}