#include <bits/stdc++.h>
using namespace std;
int main() {
  int n = 500, x = 600000;
  printf("%d\n", n);
  printf("1 1000000\n");
  for (int i = n - 2; i; i--) printf("%d %d\n", x, i), x += i * 2;
  printf("1000000 1000000\n");
  return 0;
}
