java 如何读取整数、双精度和字符串并将其保存到变量中？
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How to read and save an Integer, Double, and String to a variable?
提问by dabberson567
For a online course I'm taking,I'm trying to save the 2nd set of integer, double, and string that I defined to variables, after reading them (the 2nd set) using a scanner. The problem is I don't know how to do that to the 2nd set of variables that I defined. I've tried instantiating them to a new variable,but I keep running into errors. I need help to read each variable and then save them.
对于我正在参加的在线课程，在使用扫描仪读取它们（第二组）后，我试图将我定义的第二组整数、双精度和字符串保存到变量中。问题是我不知道如何处理我定义的第二组变量。我尝试将它们实例化为一个新变量，但我一直遇到错误。我需要帮助来读取每个变量然后保存它们。
import java.io.*;
import java.util.*;
import java.text.*;
import java.math.*;
import java.util.regex.*;
public class Solution {
public static void main(String[] args) {
int i = 4;
double d = 4.0;
String s = "HackerRank ";
int j = 4;
double y = 9.0;
String k = "is the best place to learn and practice coding!";
int j = new j();
double y = new y();
String k = new k();
j.scanner.nextInt();
y.scanner.nextDouble();
k.scanner.nextLine();
System.out.print(j + i);
System.out.print(d + y);
System.out.print(s + k);
回答by Peter Lawrey
You use assignment without declaring the type again.
您无需再次声明类型即可使用赋值。
int j = 4;
double y = 9.0;
String k = "is the best place to learn and practice coding!";
j = scanner.nextInt();
y = scanner.nextDouble();
k = scanner.nextLine();
回答by Rishi Kumar J H
A call to nextLine() may return an empty string if there are no characters between the end of the last read and the beginning of the next line.
如果在上次读取的结尾和下一行的开头之间没有字符，则对 nextLine() 的调用可能会返回一个空字符串。
s1 = scan.nextLine();
s1 = scan.nextLine();
So to complete that challenge use the above code when you read the input from the user. And the entire code goes as follows.
因此，要完成该挑战，请在读取用户输入时使用上述代码。整个代码如下。
import java.io.*;
import java.util.*;
import java.text.*;
import java.math.*;
import java.util.regex.*;
public class Solution {
public static void main(String[] args) {
int i = 4;
double d = 4.0;
String s = "HackerRank ";
Scanner scan = new Scanner(System.in);
int i1;
double d1;
String s1;
i1 = scan.nextInt();
d1 = scan.nextDouble();
s1 = scan.nextLine();
s1 = scan.nextLine();
System.out.println(i+i1);
System.out.println(d+d1);
System.out.println(s+s1);
scan.close();
}
}
回答by sui_generis
int j = 12;
double y = 4.0;
String k = "is the best place to learn coding!";
Scanner scanner = new Scanner( System.in );
j = Integer.parseInt(scanner.nextLine());
y = Double.parseDouble(scanner.nextLine());
k = scanner.nextLine();
//Ensure you print in new line
System.out.print(j + i);
System.out.print("\n");
System.out.print(d + y);
System.out.print("\n");
System.out.print(s + k);
回答by Praveen Narwal
int k = scan.nextInt();
double l = scan.nextDouble();
scan.nextLine();
String f = scan.nextLine();
System.out.println(k + i);
System.out.println(l + d);
System.out.println(s+f);
回答by CdrAshw
The following code will give you the result
下面的代码会给你结果
int j;
double y;
String k=null;
Scanner scan = new Scanner(System.in);
j= scan.nextInt();
y=scan.nextDouble();
while(scan.hasNext()){
k =scan.nextLine();
}
System.out.println(i+j);
System.out.println(d+y);
System.out.println(s+k);
回答by user6252820
int i1= sc.nextInt();
double d1 = sc.nextDouble();
String s1 = sc.next();
System.out.println(i+i1);
System.out.println(d+d1);
System.out.println(s+s1);
you can also follow this if u don't have any spaces for your s1 string.
如果您的 s1 字符串没有任何空格，您也可以按照此操作。
回答by Ridhi Vats
import java.io.*;
import java.util.*;
import java.text.*;
import java.math.*;
import java.util.regex.*;
public class Solution {
public static void main(String[] args) {
int i = 4;
double d = 4.0;
String s = "HackerRank ";
Scanner scan = new Scanner(System.in);
int j = 4;
double y = 9.0;
String k = "is the best place to learn and practice coding!";
Scanner f = new Scanner(System.in);
j = Integer.parseInt(f.nextLine());
y = Double.parseDouble(f.nextLine());
k = f.nextLine();
System.out.println(j + i);
System.out.println(d + y);
System.out.println(s + k);
scan.close();
}
}
}
回答by theVoid
All you need to do is the following:
您需要做的就是以下几点：
Scanner scanner = new Scanner(System.in);//instantiate a Scanner object
int j = scanner.nextInt();//Use the Scanner object to read an int value from the user
double y = scanner.nextDouble();//Use the Scanner object to read an double value from the user
String k = scanner.nextLine();//Use the Scanner object to read an line from the user
回答by Lakmal Vithanage
import java.io.*;
import java.util.*;
import java.text.*;
import java.math.*;
import java.util.regex.*;
public class Solution {
public static void main(String[] args) {
int i = 4;
double d = 4.0;
String s = "HackerRank ";
int j = 4;
double y = 9.0;
String k = "is the best place to learn and practice coding!";
Scanner s = new Scanner(System.in);
j = Integer.parseInt(s.nextLine());
y = Double.parseDouble(s.nextLine());
k = s.nextLine();
System.out.print(j + i);
System.out.print(d + y);
System.out.print(s + k);
}
}
