#include <iostream>
#include <random>
#include <cassert>
#include <chrono>
std::mt19937 rng(std::chrono::high_resolution_clock::now().time_since_epoch().count());
int random(int l, int r) {
assert(l <= r);
return std::uniform_int_distribution<int>(l, r)(rng);
}
int main() {
std::ios::sync_with_stdio(false);
std::cin.tie(0);
int n = 100000;
std::cout << n << '\n';
int s = (int) sqrt(n);
for (int i = 1; i <= s; i++) {
std::cout << i << ' ';
}
for (int i = 1; i <= n; i++) {
std::cout << random(1, n) << ' ';
}
return 0;
}
