java 多线程 求和

java 多线程 求和

帮你帮到底，你凑合着看看吧

package test;

import java.io.*;

class testthread
extends Thread {
int b[] = null;
public testthread(int[] a) {
b = a;
}

public void run() {
int sum = 0;
for (int i = 0; i < b.length; i++) {
sum = sum + b[i];
}
System.out.println(sum);
thread.tnumInc(sum);
}
}

public class thread {
private static int ready = 0;
private static int tnum = 0;
private static int SUM = 0;
static synchronized void tnumInc(int p)
{
ready++;
SUM += p;
if(ready>=tnum){
System.out.println(SUM);
}
}

public static void main(String args[]) {
// TODO 自动生成方法存根
try {
System.out.print("输入线程数 p(p>=2)：");
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
String A = (String) br.readLine();
int p = Integer.parseInt(A);
tnum = p;
System.out.print("输入求和数 n：");
BufferedReader cr = new BufferedReader(new InputStreamReader(System.in));
String B = (String) cr.readLine();
String x[] = B.split(" ");
int[] n = new int[x.length];
for (int i = 0; i < x.length; i++) {
n[i] = new Integer(x[i]).intValue();
}
int c = n.length / p;
int a[][] = new int[p][c]; //定义一个多维数组
int b = 0;
for (int i = 0; i < p; i++) //将n[]中元素赋值给多维数组
for (int j = 0; j < c; j++) {
a[i][j] = n[b];
b++;
}
for (int i = 0; i < p; i++) { //测试多维数组输出
for (int j = 0; j < c; j++) {
System.out.print(a[i][j] + " ");
}
System.out.println();
}
for (int i = 0; i < p; i++) //创建线程
new testthread(a[i]).start();

}
catch (IOException e) {}

}

}

随便写写，没有测试过。你自己调调看吧。

大概思路就是给一个方法合并结果，并对已经完成的thread进行计数

当完成的thread的数量==总数的时候，最后结果就出来了