Linux 进程 分配法分配质数计算

#include<stdio.h>
#include<stdlib.h>
#include<unistd.h>
#include<sys/types.h>
#include<sys/wait.h>
#define LEFTNUM 3000000
#define RIGHTNUM 3000200
#define N 3
int main(int argc,char** argv)
{
        int mark=0;
        pid_t pid;
        for(int n=0;n<N;n++)
        {
                pid=fork();
                if(pid<0)
                {
                        perror("fork()");
                        exit(1);
                }
                if(pid==0)
                {
                        //分配法分配数
                        for(int i=LEFTNUM+n;i<=RIGHTNUM;i+=N)
                        {
                                mark=1;
                                for(int j=2;j<i/2;j++)
                                {
                                        if(i%j==0)
                                        {
                                                mark=0;
                                                break;
                                        }
                                }
                                if(mark==1)
                                {
                                        //n展示哪一个进程进行计算//结果可得0进程不存在质数
                                        printf("[%d]%d is a primer!\n",n,i);
                                }
                        }
                        exit(0);
                }
        }
        //給子进程收尸
        for(int n=0;n<N;n++)
                wait(NULL);
        exit(0);
}

结果：

book@100ask:~/tmpfile/process_basic$ ./forkwait0
[2]3000017 is a primer!
[1]3000061 is a primer!
[2]3000029 is a primer!
[1]3000073 is a primer!
[2]3000047 is a primer!
[1]3000103 is a primer!
[1]3000133 is a primer!
[2]3000077 is a primer!
[2]3000089 is a primer!
[1]3000181 is a primer!
[1]3000199 is a primer!
[2]3000131 is a primer!
[2]3000161 is a primer!
book@100ask:~/tmpfile/process_basic$ ./forkwait0 |wc -l
13