Write a program to open 3 threads, the IDs of the 3 threads are a, B, C, each thread prints its own ID on the screen 10 times

Write a program, open 3 threads, the IDs of the 3 threads are a, B, C, each thread prints its own ID on the screen 10 times, the output must be displayed in the order of ABC, such as: Abcabc .... recursion in turn. #include  <stdio.h>    #include  <stdlib.h>    #include  <pthread.h >    #include  <unistd.h>    #include  <string.h>   //#define  debug 1    #define &NBSP;NUM&NBSP;3       int n=0;   pthread_ mutex_t mylock=pthread_mutex_initializer;//Mutex    Pthread_cond_t qready=pthread_cond_ initializer;//condition variables          void * thread_func (void *arg)    {       int param= (int) arg;       char c= ' A ' +param;       int ret,i=0;       for  (;  i < 10; i++)        {            pthread_mutex_lock (&mylock);   &NBSP;&NBSP;&NBSP;&NBSP;&NBSP;&NBsp;  while  (param != n)   //just running, n = 0, param = 0, Conditions are not set, so print directly a           {   #ifdef  debug                 printf ("thread %d  Waiting\n ",  param);   #endif                 ret = pthread_cond_wait (&qready, &mylock);                if  (ret == 0)                 {   #ifdef  debug     &NBSP;&NBSP;&NBSP;&NBSP;&NBSP;&NBSP;&NBSP;&NBSP;&NBSP;&NBSP;&NBSP;&NBSP;&NBSP;&NBSP;&NBSP;&NBSP;PRINTF (" Thread %d wait success\n ",  param);   #endif                 } else                 {   #ifdef  debug                     printf ("thread %d wait failed:%s\n" ,  param, strerror (ret));   #endif                 }           }           // printf ("%d ", param+1);            printf ("%c ", c);   //print a after             n= (n+1)%num;      //n became 1, The impact on thread 2 will be output ....            pthread_mutex_unlock (&mylock);           //will wake up all the threads, because when the thread finishes, it waits for pthread_cond_wait () to execute two times before exiting while  (param != n)             pthread_cond_broadcast (&qready);                   }            return  (void *) 0;  }      #if  0   // assumed to be thread 2       void * thread_func (VOID&NBSP;*ARG)//Incoming value 1   {       int param= (int) arg;       char c= ' A ' +param;        int ret,i=0;       for  (;  i  < 10; i++)        {            pthread_mutex_lock (&mylock);            while  (PAram != n)   //and thread 1 are executed at the same time, so the initial condition is met             {   #ifdef  debug                 printf ("thread %d waiting\n",  param);   #endif                 //execution to this point, waiting for thread 1 to send a signal, when a thread 1 of a print, the value of n also becomes 1, the condition is not established                ret = pthread_ Cond_wait (&qready, &mylock);                if  (ret == 0)                  {   #ifdef  debug                     printf ("thread %d wait success\n",  param);    #endif                } else                 {   #ifdef   DEBUG                     printf ("thread %d wait failed:%s\n",  param, strerror (ret));   #endif                }            }          // printf ("%d   ", param+1);           printf ("%c  ", c);  // This prints the value b           n= (n+1)%num;    // Impact on thread 3 printing c ...            pthread_mutex_unlock (&mylock);   &NBSp;       pthread_cond_broadcast (&qready);        }           return  (void *) 0;   }      #endif       int main (int argc, char**  argv)  {              int i=0,err;        pthread_t tid[NUM];       void *tret;        for (; i<num;i++)        {            err=pthread_create (&tid[i],null,thread_func, (void *) i);            if (err!=0)             {                printf ("Thread_create error:%s\n ", strerror (Err));                exit ( -1);           }        }       for  (i = 0; i < num; i+ +)        {           err =  pthread_join (Tid[i], &tret);           if   (err != 0)            {                printf ("Can not join with  thread %d:%s\n ",  i,strerror (Err));                exit ( -1);           }       }       printf ("\ n");       return 0;   }  

#include <stdio.h> #include <stdlib.h> #include <pthread.h> #include <unistd.h> #include <
string.h>//#define DEBUG 1 #define NUM 3 int n=0; pthread_mutex_t mylock=pthread_mutex_initializer;//Mutex pthread_cond_t qready=pthread_cond_initializer;//condition variable void *
    Thread_func (void *arg) {int param= (int) arg;
    Char c= ' A ' +param;
    int ret,i=0;
        for (; i <; i++) {pthread_mutex_lock (&mylock);  while (param! = N)//Just run, n = 0, param = 0, the condition is not true, so print a {#ifdef DEBUG printf ("Thread%d waiting\n") directly,
param);
            #endif ret = pthread_cond_wait (&qready, &mylock); if (ret = = 0) {#ifdef DEBUG printf ("Thread%d wait success\n", param); #endif}
            else {#ifdef DEBUG printf ("Thread%d wait failed:%s\n", Param, strerror (ret)); #endif
        }}//printf ("%d", param+1);  printf ("%c", c); After printing a
        N= (n+1)%num;
        n becomes 1, which affects the output of thread 2 ....
		Pthread_mutex_unlock (&mylock);
		
    All threads are awakened because when the thread finishes it waits for pthread_cond_wait () to execute two times before exiting while (param! = N) pthread_cond_broadcast (&qready);
} return (void *) 0;
    } #if 0//assumed to be thread 2 void * Thread_func (void *arg)//Incoming value 1 {int param= (int) arg;
    Char c= ' A ' +param;
    int ret,i=0;
        for (; i <; i++) {pthread_mutex_lock (&mylock);
			while (param! = N)//and thread 1 are executed concurrently, the conditions at the beginning of the condition satisfy {#ifdef DEBUG printf ("Thread%d waiting\n", param); #endif
            Execution to this point, waiting for thread 1 to send a signal, when thread 1 of a print, the value of n also becomes 1, the condition does not set up ret = Pthread_cond_wait (&qready, &mylock);
            if (ret = = 0) {#ifdef DEBUG printf ("Thread%d wait success\n", param); #endif
            } else {#ifdef DEBUG printf ("Thread%d wait failed:%s\n", Param, strerror (ret)); #endif
        }}//printf ("%d", param+1); Printf("%c", c);    At this time the print value B n= (n+1)%num;
        Impact on thread 3 printing c ...
        Pthread_mutex_unlock (&mylock);
    Pthread_cond_broadcast (&qready);
} return (void *) 0;
    } #endif int main (int argc, char** argv) {int i=0,err;
    pthread_t Tid[num];
    void *tret;
        for (; i<num;i++) {Err=pthread_create (&tid[i],null,thread_func, (void *) i);
            if (err!=0) {printf ("Thread_create error:%s\n", strerror (err));
        Exit (-1);
        }} for (i = 0; i < NUM; i++) {err = Pthread_join (Tid[i], &tret);
            if (err! = 0) {printf ("Can not join with thread%d:%s\n", I,strerror (err));
        Exit (-1);
    }} printf ("\ n");
return 0; }

The results are as follows: