用Java编写程序 任意两个输入两个整数 输出它们相加的结果

Question

import java.util.Scanner;

public class java4 {

public static void main(String[] args) {

Scanner i=new Scanner(System.in);
int a=i.nextInt();
int b=i.nextInt();
if(a>100&&a<10);
{System.out.println("输入错误，请输入两位数！");
};

if(b>100&&b<10);
{System.out.println("输入错误，请输入两位数！");}

{System.out.println(a+b);}
}

}
帮忙改下吧，谢谢啦！

Answer 1

import java.util.Scanner;

public class Program1 {

public static void main(String[] args) {

Scanner i = new Scanner(System.in);

int a = i.nextInt();

int b = i.nextInt();

if (a > 100 || a < 10 || b>100 ||b<10) {

System.out.println("输入错误，请输入两位数！");

}else{

System.out.println(a + b);

}

}

}

扩展资料：

java的用法小结

一、简单的stream，parallelStream慎用

List<Integer> list = Arrays.asList(1, 2, 3, 4, 5, 6, 7, 8);

list.parallelStream().forEach(System.out::println);

list.parallelStream().forEachOrdered(System.out::println);

二、简单的stream, collect, sum, count,

1、取某一字段 stream & collect

System.out.println(userList.stream().map(User::getAddress).collect(Collectors.toList()));

System.out.println("---------");

ArrayList<String> arrayList = 

userList.stream().map(User::getAddress).collect(Collectors.toCollection(ArrayList::new));

System.out.println(arrayList);

System.out.println("---------");
System.out.println(userList.stream().map(User::getAddress).collect(Collectors.joining("@@")));

2、取总和 sum

System.out.println(userList.stream().mapToInt(User::getAge).sum());

3、分组

Map<String, List<User>> addressMap = 

userList.stream().collect(Collectors.groupingBy(User::getAddress));

System.out.println(addressMap);

Answer 2

import java.util.Scanner;
public class java4 {
public static void main(String[] args) {
Scanner i=new Scanner(System.in);
int a=i.nextInt();
int b=i.nextInt();
if(a>100||a<10){
System.out.println("输入错误，请输入两位数！");
}
else if(b>100||b<10){
System.out.println("输入错误，请输入两位数！");
}
else
System.out.println(a+b);
}
}
注意你的几处错误，||才是或的意思。

Answer 3

import java.util.Scanner;

public class Add{

　　public static void mian(String[] args) {

　　　　  System.out.println("请输入被加数a：");

                       Scanner scanner1 = new Scanner(System.in);
       

                       int num1 = scanner1.nextInt();

                       System.out.println("请输入被加数b");
                       Scanner scanner2 = new Scanner(System.in);
       

                       int num2 = scanner2.nextInt();

                       int sum = add(num1,num2);
                       System.out.println("a + b = " + sum);
   
       }
   
       static int add(int a, int b) {
               return a+b;
       }

}

Answer 4

package basic.aSelf;
import java.util.Scanner;
public class AnyNOPlus {
/**
* @param args
*/
public static void main(String[] args) {
// System.out.println(invertStr("12345"));
Scanner s=new Scanner(System.in);
String str1=s.nextLine();
String str2=s.nextLine();
System.out.println(AnyNOPlusDemo(str1,str2));
}
/**
* 实现任意两个整数相加
* @param str1
* @param str2
* @return
*/
public static String AnyNOPlusDemo(String str1,String str2){
str1=invertStr(str1);//4321
str2=invertStr(str2);//1
//判断谁的长度长
char[] charMaxLength;
char[] charMinLength;
if(str1.length()>=str2.length()){
charMaxLength=str1.toCharArray();
charMinLength=str2.toCharArray();
}else{
charMaxLength=str2.toCharArray();
charMinLength=str1.toCharArray();
}
//进位
int other=0;
//返回的String
String strAll="";
//相加
int c=0;
int c1=0;
int c2=0;
for(int i=0;i<charMaxLength.length;i++){
c1=charMaxLength[i]-'0';
if(i<charMinLength.length){
c2=charMinLength[i]-'0';
}else{
c2=0;
}
c=(other+c1+c2)%10;
//判断进位
if(other+c1+c2>=10){
other=1;
}else{
other =0;
}
//相加
strAll+=c;
}
return invertStr(strAll);
}
/**
* 将字符串倒转
* @param str
* @return
*/
public static String invertStr(String str){
String result="";
for(int i=str.length()-1;i>=0;i--){
char c=str.charAt(i);
result+=c;
}
return result;
}
}

Answer 5

完整代码如下:

package testcode;  

import java.util.Scanner;  

public class PAT1001 {  

public static void main(String[] args) {  

// TODO Auto-generated method stub  

Scanner scanner=new Scanner(System.in);  

int a=Integer.parseInt(scanner.next());  

int b=Integer.parseInt(scanner.next());  

Integer c=a+b;  

String s =  c.toString();  

char[] strings2 = s.toCharArray();  

int num;  

char[] output;  

int i=0,k;  

if (strings2[0]=='-') {  

if ((strings2.length-1)%3==0) {  

num=(strings2.length-4)/3;  

}else {  

num=(strings2.length-1)/3;  

}  

output=new char[strings2.length+num];  

i=0;  

k=output.length;  

for (int j = strings2.length-1; j >=0 ; j--) {  

i++;  

k--;  

if (i%3==0&&k>=2) {  

output[k]=strings2[j];  

k--;  

if(k>=0){  

output[k]=',';  

}  

}else{  

output[k]=strings2[j];  

}  

}  

}else{  

if (strings2.length%3==0) {  

num=(strings2.length-3)/3;  

}else {  

num=strings2.length/3;  

}  

output=new char[strings2.length+num];  

i=0;  

k=output.length;  

for (int j = strings2.length-1; j >= 0; j--) {  

i++;  

k--;  

output[k]=strings2[j];  

if(i%3==0){  

k--;  

if(k>=0){  

output[k]=',';  

}  

}  

}  

}  

System.out.println(output);   

}  

}  

拓展:程序目的是将形如-23455066，2345539转化成-23,455,066，2,345,539形式。用到的主要方法是String的toCharArray()方法，该方法将字符串转化成字符数组，获取到数组后就可以利用其进行修改，