小编Woo*_*ung的帖子

在这种情况下,MAX只有5,所以我可以逐个检查重复,但我怎么能以更简单的方式做到这一点？例如,如果MAX的值为20,该怎么办？谢谢.

int MAX = 5;

for (i = 1 , i <= MAX; i++)
{
        drawNum[1] = (int)(Math.random()*MAX)+1;

        while (drawNum[2] == drawNum[1])
        {
             drawNum[2] = (int)(Math.random()*MAX)+1;
        }
        while ((drawNum[3] == drawNum[1]) || (drawNum[3] == drawNum[2]) )
        {
             drawNum[3] = (int)(Math.random()*MAX)+1;
        }
        while ((drawNum[4] == drawNum[1]) || (drawNum[4] == drawNum[2]) || (drawNum[4] == drawNum[3]) )
        {
             drawNum[4] = (int)(Math.random()*MAX)+1;
        }
        while ((drawNum[5] == drawNum[1]) ||
               (drawNum[5] == drawNum[2]) ||
               (drawNum[5] == drawNum[3]) ||
               (drawNum[5] == drawNum[4]) )
        {
             drawNum[5] = (int)(Math.random()*MAX)+1; …

public class NaiveAlien extends Alien
{

    @Override
    public void harvest(){}

}

我试图理解我朋友的代码,但我没有在代码中获得语法@Override.这是做什么的,为什么我们需要编码？谢谢.

int[] alist = new int [3];
alist.add("apple");
alist.add("banana");
alist.add("orange");

假设我想使用ArrayList中的第二项.为了获得以下输出,编码是什么？

输出:

香蕉

过程和模块的公共或私有的默认值？

谢谢.

int main (void)
{
   int i;
   for (i=1; i<=20; i++) {
       int j;
       unsigned long long fac = 1;

       for ( j = 1; j<=i; ++j) {
          fac *= j;
       }

       printf ("%2i! = %ld\n", i, fac);
    }

return 0;
}

从14开始!到20!输出错误的值.

它要么给出一个负数,要么数字不够大..问题是什么？

 #include <stdio.h>
 #include <string.h>
 #include <malloc.h>

struct Student {
       char name[100];
       int id;
       char major[50];
       char address[200];
};

int main()
{

     struct Student st;

     strcpy(st.name, "Chuck");
     st.id = 20001;
     strcpy(st.major, "Computer Science");
     strcpy(st.address, "1st Street");

     printf("%d %d %d %d %d\n", sizeof(st), sizeof(st.name),sizeof(st.id), sizeof(st.major), sizeof(st.address));

     return 0;
}

输出为356 100 4 50 200.为什么sizeof(st)356,而不是354？我尝试了这个没有int,输出是350 100 50 200,所以我假设问题在整数.

这是我关于 setter 和 getter 的任务，由于某种原因它不起作用。谁能检查一下我的问题是什么？谢谢你。

public class FlightTest
{
    public static void main (String [] args)
    {

        String name;
        String number;
        String Orig;
        String Desti;

        Scanner scan = new Scanner (System.in);

        Flight data = new Flight ();

        System.out.print ("Airline Name: ");
        String AirlineName = scan.nextLine ();
        data.setAirlineName (name);

        System.out.print ("Flight Number: ");
        String FlightNumber = scan.nextLine ();
        data.setFlightNumber (number);

        System.out.print ("Origin: ");
        String Origin = scan.nextLine();
        data.setOrigin (Orig);

        System.out.print ("Destination: ");
        String Destination = scan.nextLine ();
        data.setDestination (Desti);

        System.out.println (data); …

编译此代码时出现以下消息.

Question2中的ExtractChars(java.lang.String,int)无法应用于()

我该怎么办？

谢谢.

import java.util.Scanner;

public class Question2
{

    public static void main (String[] args)
    {

        ExtractChars();

    }
    public static String ExtractChars(String sOrg, int startPos)
    {

        Scanner scan = new Scanner (System.in);
        String value = "";
        System.out.print("Enter a string: ");
        sOrg = scan.next();
        System.out.print("/nEnter an integer: ");
        startPos = scan.nextInt();
        if (sOrg.length()<=startPos)
        {

            value = "";

        }
        else
        {
            for (int i=startPos; i<sOrg.length();i=i+2)
            {

                value = value + sOrg.charAt(i);

            }
        }

        return value;
    }
}