#include <stdlib.h>
#include <stdio.h>
#include <stdbool.h>
#include <pthread.h>
#include <unistd.h>

struct string_sleep {
    char* string;
    unsigned int seconds;
};

void* print_sleep(void* arg) {
    struct string_sleep* ss = (struct string_sleep*)arg;
    while (true) {
        printf("%s", ss->string);
        fflush(stdout);
        sleep(ss->seconds);
    }
}

int main(int argc, char** argv) {
    pthread_t thd1, thd2;
    struct string_sleep zeros = {"0", 1};
    struct string_sleep ones  = {"1", 2};
    
    pthread_create(&thd1, NULL, print_sleep, &zeros);
    pthread_create(&thd2, NULL, print_sleep, &ones );
    
    void* result;
    
    pthread_join(thd1, &result);
    pthread_join(thd2, &result);
}