Java 三道难题，希望大神详细解答。拜托拜托
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Person person = New Chinese\uff08\uff09\uff1b\u591a\u6001
三个题目一起贴代码太多了， 百度不允许贴这么多代码。 只能贴前面2题的代码
第一题：
import java.util.Scanner;
/**
* @author young
* @Description: TODO
* @date 2016年5月31日下午5:52:11
*/
public class Test {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
System.out.println("Please input the number: ");
int num = sc.nextInt();
if (num < 0 || num > 1000000) {
System.out.println("Input Error");
System.exit(0);
} else {
String word = String.valueOf(num);
int i = word.length();// 获取长度
int j = 0;
while (j <= (i / 2) - 1 && word.charAt(j) == word.charAt(i - j - 1))
j++;
if (j == i / 2)
System.out.println("palindrome number.");
else
System.out.println("not palindrome number.");
sc.close();
}
}
}
第二题：
/**
* @author young
* @Description: TODO
* @date 2016年5月31日下午5:52:11
*/
public class Test {
public static void main(String[] args) {
int[] b = new int[50];
int sum = 0, avg = 0, t1 = 0, t2 = 0, t3 = 0,t4 = 0,t5 = 0;
for(int i = 0; i < b.length; i++){
// b[i] = (int)((100)*Math.random());
b[i] = (int)(0+Math.random()*(100-0+1));
sum+=b[i];
if(b[i]>=0 && b[i] < 60){
t1++;
}else if(b[i]>=60 && b[i] < 70){
t2++;
}else if(b[i]>=70 && b[i] < 80){
t3++;
}else if(b[i]>=80 && b[i] < 90){
t4++;
}else if(b[i]>=90 && b[i] <= 100){
t5++;
}
}
//每10行输出数组
int count = 1;
for(int i = 0; i < b.length; i++){
System.out.format("%4s", b[i]);
count++;
if(count%10 == 0){
System.out.println();
count = 1;
}
}
//冒泡排序 从大到小
for (int k = 0; k < b.length - 1; k++) {
for (int j = k + 1; j < b.length; j++) { // 升序把<改成>
if (b[k] < b[j]) {
int temp = b[k];
b[k] = b[j];
b[j] = temp;
}
}
}
System.out.println("
最大值：" + b[0]);
System.out.println("最小值：" + b[49]);
System.out.println("平均值：" + (sum / 50));
System.out.println("[0,60)区间个数：" + t1);
System.out.println("[60,70)区间个数：" + t2);
System.out.println("[70,80)区间个数：" + t3);
System.out.println("[80,90)区间个数：" + t4);
System.out.println("[90,100]区间个数：" + t5);
}
}
import java.util.Scanner;
/**
* 2016年6月7日下午12:11:53
*
* @author 3306 TODO something about 绿豆芽
*
*/
public class TestB1 {
private static Scanner input = new Scanner(System.in);
/**
* 输入整数
*
* @return
*/
public static long inputLong() {
long num = 0;
do {
num = input.nextLong();
if (num > 1000000 || num < 0) {
System.err.println("Input Error");
}
} while (num < 0 || num > 1000000);
return num;
}
/**
* 判断是否是回文整数
*
* @param num
* 整数
* @return
*/
public static boolean isPalindrome(long num) {
long tmp = 0;
long origin = num;
while (num > 0) {
tmp = tmp * 10 + num % 10;
num /= 10;
}
return tmp == origin;
}
public static void main(String[] args) {
long num = inputLong();
if (isPalindrome(num)) {
System.out.println("palindrome number");
} else {
System.out.println("not palindrome number");
}
}
}
第一题:
public class Palindrome {
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
System.out.println("请输入一个0-100000的数值：");
int num = input.nextInt();
if(num > 100000){
System.out.println("Input Error!");
System.exit(0);
}
String numString = Integer.toString(num);
boolean flag = false;
//比较前一半跟后一半是否相等
//numString.length()/2是因为只需要比较前一半跟后一半，循环完前一半所有的数值即可
for(int i = 1; i <= numString.length()/2; i++){
if(numString.charAt(i) == numString.charAt(numString.length()- 1 - i)){
flag = true;
}
}
if(flag){
System.out.println("palindrome number");
}else {
System.out.println("not palindrome number");
}
}
}
第二题：
public class TestB {
public static void main(String[] args) {
int sum = 0;
int c = 0,a1 = 0,a2 = 0,a3 = 0,a4 = 0,a5 = 0,a6 =0;
int[] b = new int[50];
for(int i = 0; i <=49 ; i++){
b[i] = (int)(Math.random()*100);
if(b[i]>9){
System.out.print(b[i] + " ");
}else{
System.out.print(b[i] + " ");
}
a6++;
if(b[i] < 70 && b[i] > 60){
a2++;
}else if(b[i] < 80 && b[i] > 70){
a3++;
}else if(b[i] < 90 && b[i] > 80){
a4++;
}else if(b[i] < 100 && b[i] > 90){
a5++;
}else{
a1++;
}
if(a6%10==0){
System.out.println();
}
sum = sum + b[i];
}
Arrays.sort(b);
System.out.println("最小值：" + b[0]);
System.out.println("最大值:" + b[49]);
System.out.println("平均值是:" + sum/50 );
System.out.println("[0,60)的有:" + a1 + "个");
System.out.println("[60,70)的有:" + a2 + "个");
System.out.println("[70,80)的有:" + a3 + "个");
System.out.println("[80,90)的有:" + a4 + "个");
System.out.println("[90,100)的有:" + a5 + "个");
}
}
第三题：
public class Student {
private String id;
private String name;
public Student(String n,String i){
this.id = i;
this.name = n;
}
public String getId() {
return id;
}
public void setId(String id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public void disp(){
System.out.print(name + "的id号是:" + id );
}
}
public class Undergraduate extends Student{
public static void main(String[] args) {
Undergraduate u = new Undergraduate("张三", "101", 85, 90);
u.disp();
}
private int maths;
private int computer;
public int getMaths() {
return maths;
}
public void setMaths(int maths) {
this.maths = maths;
}
public int getComputer() {
return computer;
}
public void setComputer(int computer) {
this.computer = computer;
}
public Undergraduate(String n,String i,int m, int c){
super(n,i);
this.maths = m;
this.computer = c;
}
@Override
public void disp() {
// TODO Auto-generated method stub
super.disp();
System.out.print("数学成绩是" + maths + ",电脑成绩是:" + computer);
}
}
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