A random number generator.

random_generator.cpp

#include <iostream>
#include <cstdio>
#include <cstring>
#include <cstdlib>
#include <ctime>
using namespace std;

const int MOD = 10;

int main() {
  freopen("test.txt", "w", stdout);

  srand((int)time(0));
  int T = 1000;

  cout << T << endl;
  for (int i = 0; i < T; ++i) {
    int n = rand()%MOD + 5; 
    cout << n << endl;
    for (int j = 0; j < n; ++j)
      cout << rand()%MOD - 5 << " ";
    cout << endl;
  }
  return 0;
}