import java.util.*;

class MaximumElement extends Thread{

int dt[];

int a,b;

public MaximumElement(int f[],int a, int b){

dt = f;

this.a = a;

this.b = b;

}

public void run(){

for(int i = a; i < b ; i++){

int j = i; int k = i+1;

while(k<b){

if (dt[j] < dt[k])

j= k ;

else

;

k++;

}

int temp = dt[i]; dt[i] = dt[j]; dt[j] = temp;

}

}

public int getMax(){

return dt[a];

}

}

class Q2{

public static void main(String args[]){

int f[] = new int[1000];

Random r = new Random();

for(int j = 0; j < f.length;j++)

f[j]=r.nextInt(1000);

MaximumElement t1 = new MaximumElement(f,0,500);

MaximumElement t2 = new MaximumElement(f,500,1000);

t1.start();

t2.start();

try{

t1.join();

t2.join();

}catch(InterruptedException e){

}

for(int i = 0 ; i < f.length; i++){

if(i==50)

System.out.println();

System.out.println(f[i]+"");

}

System.out.println("Max number in t1 is"+t1.getMax());

System.out.println("Max number in t2 is"+t2.getMax());

if(t1.getMax() >= t2.getMax())

System.out.println(t1.getMax());

}

}

A program is required to find the Maximum element in a large array. This program will be excuted on a dual-core machine and should be written in such a way as to use both cores to optimize the solution. Your task is to write the program.
这个是题目！

for(int i = a; i < b ; i++){
int j = i; int k = i+1;
while(k<b){
if (dt[j] < dt[k])
j= k ; //这样做岂不乱套,连循环变量都改变了.
else
; //如果是;那还不如不写else
k++;
}

你应该是想把最大的数一直保存在dt[a] 中.(貌似却又是排序)
可以这样.
int k=i+1;
while(k<b)
{
if(dt[k]>dt[a])
{
int temp=dt[k],dt[k]=dt[a],dt[a]=temp;
}
k++;
}