Java - 生成随机数并对每个值进行分类

Question

我是 Java 新手。因此，我想做的就是创建一个生成 25 个随机 int 值的程序，并使用 if-else 语句将每个值分类为大于、小于或等于第二个随机生成的值。我想使用数组来访问每个元素，但我不确定除了使用数组之外还能做什么。

import java.util.Random;

public class main {

    public static void main(String[] args){
        Random rand = new Random();
        int[] randNumber = new int[25];

        for (int i = 0; i<25; i++){
            randNumber[i] = rand.nextInt(100);
        }

        if (randNumber[i]<randNumber[i+1]){
            System.out.println("Number " + randNumber[i] + "smaller than " + randNumber[i+1]);
        }
        else if(randNumber[i]>randNumber[i+1]){
            System.out.println("Number" + randNumber[i] + "greater than" + randNumber[i+1]);
        }else if(randNumber[i] == randNumber[i+1]){
            System.out.println("Number " + randNumber[i] + "equal to " + randNumber[i+1]);
        }else{
            System.out.println("Wrong!");
        }

    }
}

我知道 if-else 部分是完全错误的，但我不知道如何访问数组并比较它们。当我编译时，它会创建 25 个随机数，但在打印部分总是显示

数字 x 大于 0

因此，[i+1] 始终视为零。

非常感谢

更新

感谢 Dawood ibn Kareem 的回答，我最终创建了 2 个 for 循环。

for (int i = 0; i<25; i++){
            randNumber[i] = rand.nextInt(100);
}

for(int i = 0; i<25; i++) {
            if (randNumber[i] < randNumber[i + 1]) {
                System.out.println("Number " + randNumber[i] + " smaller than " + randNumber[i + 1]);
            } else if (randNumber[i] > randNumber[i + 1]) {
                System.out.println("Number " + randNumber[i] + " greater than " + randNumber[i + 1]);
            } else if (randNumber[i] == randNumber[i + 1]) {
                System.out.println("Number " + randNumber[i] + " equal to " + randNumber[i + 1]);
            } else {
                System.out.println("Wrong!");
            }
 }

输出看起来像这样；

Number 47 equal to 47
Number 47 smaller than 90
Number 90 greater than 84
Number 84 greater than 50
Number 50 greater than 29
Number 29 smaller than 42
Number 42 smaller than 51
Number 51 smaller than 92
Number 92 greater than 8
Number 8 smaller than 31
Number 31 smaller than 87
Number 87 greater than 10
Number 10 smaller than 80
Number 80 greater than 56
Number 56 greater than 49
Number 49 smaller than 63
Number 63 greater than 33
Number 33 smaller than 64
Number 64 greater than 25
Number 25 smaller than 87
Number 87 greater than 16
Number 16 smaller than 65
Number 65 greater than 15
Number 15 smaller than 44

但是我有一个错误说；

线程“main”中的异常java.lang.ArrayIndexOutOfBoundsException： main.main(main.java:15) 处长度 25 的索引 25 超出范围

Answer 1

运行 for 循环 24 次而不是 25 次，因为如果 i = 24，则索引 randNum[24] 处没有数组值（数组索引从 0 开始）（当您在 if 语句中执行 i+1 时）。

for (int i = 0; i < 24; i++)
{
  //your if-else blocks
}

Answer 2

我想使用数组来访问每个元素，但我不确定除了使用数组之外还能做什么。

好吧，如果您的要求是在没有数组的情况下执行此操作 - 您可以生成数字并立即检查该数字是否等于或大于或小于前一个数字：

int n = 25;
int previous = rand.nextInt(100);
for (int i = 0; i < n - 1; i++) {
    int current = rand.nextInt(100);
    
    String comparison;
    if (previous < current) {
        comparison = "smaller than";
    }
    else if (previous > current) {
        comparison = "greater than";
    }
    else {
        comparison = "equal to";
    }
    System.out.println(String.format("Number %s %s %s", previous, comparison, current));

    previous = current;
}

Answer 3

ну что вы！ все гораздо проще!

导入java.util.*;

公共课主课{

public static void main(String[] args){
int firstInt = randomInt();
        System.out.print(firstInt);
    for(int i = 1; i <= 25; i++){
        
        int secondInt = randomInt();
        if (secondInt>firstInt){
            System.out.print(" < " + " " + secondInt + " ");
        }else if(firstInt>secondInt){
            System.out.print(" > " + " " + secondInt + " ");
        }else{
            System.out.print(" = " + " " + secondInt + " ");
        }
        firstInt = secondInt;
    }
    
    
}

static int randomInt(){
    Random rand = new Random();
    return rand.nextInt(1, 25);
}

}