多線程並行計算數據總和 C語言demo

多線程計算整型數組數據總和：

#include <stdio.h>
#include <stdlib.h>
#include <Windows.h>
#include<process.h>
#include <time.h>
#define N 1024

struct Myinfo
{
    int *pstart;//開始地址
    int length;//長度
    int id;//線程編號
    int sum;//存儲數據的和
};
void  add(void *p) //void *p可以保存任何類型的指針
{
    struct Myinfo *pinfo = p;
    for (int i = 0; i < pinfo->length;i++)
    {
        pinfo->sum += pinfo->pstart[i];
    }
    printf("\n線程%d計算的結果%d", pinfo->id, pinfo->sum);
}

void main()
{
    time_t ts;
    unsigned int num = time(&ts);//傳遞地址
    srand(num);
    int data[N] = { 0 };
　　 // 進行賦值
    for (int i = 0; i < N; i++)
    {
        data[i] = rand() % 1000;
        //printf("%4d", data[i] = rand() % 1000);
    }
    int sum = 0;
　　 //計算總和
    for (int i = 0; i < N; i++)
    {
        sum += data[i];
    }
    printf("\n總和=%d", sum);

    struct Myinfo info[8] = { 0 };
    for (int i = 0; i < 8;i++)
    {
        info[i].id = i;
        info[i].length = N / 8;
        info[i].sum = 0;
        info[i].pstart = data + i*N / 8; //註意這裡地址的移動
        _beginthread(add, 0, &info[i]);
    }
    system("pause");

    int lastsum=0;
    for (int i = 0; i < 8;i++)
    {
        lastsum += info[i].sum;
    }
    printf("\n多線程總和=%d", lastsum);
    system("pause");
}

在此也可以結合隊列來使用