#include <iostream>
#include <algorithm>
#include <sstream>

class PrimeNumberGenerator {
 public:
  explicit PrimeNumberGenerator(int start) {
    this->last = start;
  }

  int GetNextPrime() {
    int n = this->last;
    int i = 2, j = 0;
    while (true) {
      if (i * i <= n && j != 1) {
        if (n % i == 0) {
          j = 1;
          i++;
        } else {
          i++;
        }
      } else if (j == 1) {
        n++;
        this->last++;
        i = 2;
        j = 0;
        continue;
      } else {
        this->last++;
        return n;
      }
    }
  }

  int last;
};