#include <iostream>

#include <ctime>

using namespace std;

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int main() {

  struct tm date;

  time_t now;

  time_t before;

​

  // Create a timestamp for right now

  time(&now);

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  // Create a timestamp for 5 hours ago

  date = *localtime(&now);

  date.tm_hour -= 5;

  before = mktime(&date);

​

  // Calculate the difference between the two timestamps in seconds

  cout << difftime(now, before);

  return 0;

}

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