53 lines
1.0 KiB
C
53 lines
1.0 KiB
C
#include <stdio.h>
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#include <stdlib.h>
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#include <unistd.h>
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#define LEFT 30000000
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#define RIGHT 30000200
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/**
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* @brief 求质数（多进程版）
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* @details
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*
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* @param argc
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* @param argv
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* @return int
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*/
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int main(int argc, char **argv)
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{
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int i, j, mark;
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pid_t pid;
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for (i = LEFT; i <= RIGHT; i++)
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{
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pid = fork( );
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if (pid < 0)
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{
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perror("fork()");
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exit(1);
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}
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if (pid == 0) // child
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{
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mark = 1;
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for (j = 2; j < i / 2; j++)
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{
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if (i % j == 0)
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{
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mark = 0;
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break;
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}
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}
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if (mark)
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printf("%d is a primer\n", i);
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sleep(1000); // * 让父进程先结束
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exit(0); // ! 退出子进程
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// ! init 在孤儿进程 exit 后才收尸
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}
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}
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// sleep(1000); // * 让子进程先结束，子进程会变成僵尸态
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exit(0);
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} |