c/c++语言开发共享记一次 c 语言 的 多线程查找 简单实现

//仅供参考学习

  1 #define _crt_secure_no_warnings //屏蔽 vs 的a   2 #include <stdio.h>   3 #include <stdlib.h>   4 #include <windows.h>   5 #include <process.h>   6 #include <time.h>   7 #include <memory.h>   8    9   10 //直接改 m_max 的值则是改变总的范围  11 #define m_max 250000 //最好是 totalthread 的整数倍  12   13   14   15 typedef struct s{  16     int *begin;//每个线程其实索引地址  17     int lenth;//索引长度  18     int target;//need find  19     int id;//thread id  20     int *flag;//线程之间通信  21     int *isfind;//附加功能标记那个线程找到的  22 }s_t;  23   24   25   26 void find(void *p)  27 {  28     s_t* ps = (s_t*)p;//indo  29   30     int* cur = null;//need find number addres  31   32     for (cur = ps->begin; cur != ps->begin + ps->lenth; ++cur)  33     {  34         if (1 == *(ps->flag))  35         {  36             char str[100] = { 0 };  37             sprintf(str, " thread %d incapable been thread %d preemptiven", ps->id, *(ps->isfind));  38             printf("%s", str);  39             _endthread();  40         }  41         if ((*cur) == ps->target)  42         {  43             printf(text("thread %d finde n"), ps->id);  44             printf(" %dn", *cur);  45             sleep(10);  46             *(ps->flag) = 1;  47             *(ps->isfind) = ps->id;  48       49             _endthread();  50         }  51     }  52     {//快语句 看起来 代码整洁  53         char str[100] = { 0 };  54         sprintf(str, " thread %.5d is incapable n", ps->id, *(ps->isfind));  55         printf("%s", str);  56     }  57   58     _endthread();  59 }  60   61   62 int main()  63 {  64     srand((unsigned int)time(null));  65   66     //需要寻找的源  67     int array[m_max];  68   69     //标志位  70     int flag = 0;  71     int isfind = 0;  72   73     //随机的目标  74     int target = rand() % m_max;  75     printf("need find number is %d n", target);  76   77   78     int totalthread = 50;  79   80     //线程需要的信息   81     s_t s[50];    //设定线程个数    ## 这里的 50 与 totalthread 变量是相关的 要改都改  82       83     int divideddatasize = (m_max / totalthread);        //设定每个线程需要索引的大小   84   85   86     //随机初始化 源内的数据  87     for (int j = 0; j < m_max; ++j) {          88         array[j] = rand()%m_max;  89     }  90   91     //初始化每个线程  92     for (int i = 0; i < totalthread; ++i)  93     {  94         s[i].begin = array + (i*divideddatasize);  95         s[i].id = i;  96         s[i].lenth = (divideddatasize);  97         s[i].target = target;  98         s[i].flag = &flag;  99         s[i].isfind = &isfind; 100         _beginthread(find, 0, &s[i]); 101         sleep(10);　　//避免出现线程访问冲突 102     } 103  104  105     system("pause"); 106     return 0; 107 }