#include "stdio.h"
#include "time.h"
// for sleep
#include "unistd.h"

int main(){

    time_t t1,t2;
    t1 =time(NULL) ;
    sleep(1);
    t2 =time(NULL) ;
    printf("%ld %ld \n",t1,t2);
    long time1 = t1;
    long time2 = t2;
    
    printf("%ld %ld \n",time1,time2);
    
    // 1631609390    s
    // java System.currentTimeMillis()
    // 1631609345307 ms  
    
    
    return 0;
}