Java 使用用户输入更改变量
嘿,我是Java编程新手,我正在努力改变变量并寻求一些帮助。问题如下: 创建一个程序,要求用户输入三个数字,然后打印它们的总和。在程序中使用以下结构:Java 使用用户输入更改变量,java,Java,嘿,我是Java编程新手,我正在努力改变变量并寻求一些帮助。问题如下: 创建一个程序,要求用户输入三个数字,然后打印它们的总和。在程序中使用以下结构: // TODO code application logic here Scanner reader = new Scanner(System.in); int sum = 0; int read;//`enter code here` // WRITE YOUR PROGRAM HERE // U
// TODO code application logic here
Scanner reader = new Scanner(System.in);
int sum = 0;
int read;//`enter code here`
// WRITE YOUR PROGRAM HERE
// USE ONLY THE VARIABLES sum, reader AND read!
System.out.println("Sum: " + sum);
这就是我在下面写的内容,当然我会遇到语法错误:
Scanner reader = new Scanner(System.in);
int sum = 0;
System.out.print("Type the first Number: ");
int read = Integer.parseInt(reader.nextLine());
System.out.print("Type the second number: ");
int read = read + (Integer.parseInt(reader.nextLine()));
System.out.print("Type the third number: ");
int read = read + (Integer.parseInt(reader.nextLine()));
sum = read;
System.out.println("Sum: " + sum);
您的代码应该类似于:
Scanner reader = new Scanner(System.in);
int sum = 0;
System.out.print("Type the first Number: ");
int read = Integer.parseInt(reader.nextLine());
System.out.print("Type the second number: ");
read = read + (Integer.parseInt(reader.nextLine()));
System.out.print("Type the third number: ");
read = read + (Integer.parseInt(reader.nextLine()));
sum = read;
System.out.println("Sum: " + sum);
由于变量read
被多次声明,因此出现语法错误
您还可以使用:
您的代码应该类似于:
Scanner reader = new Scanner(System.in);
int sum = 0;
System.out.print("Type the first Number: ");
int read = Integer.parseInt(reader.nextLine());
System.out.print("Type the second number: ");
read = read + (Integer.parseInt(reader.nextLine()));
System.out.print("Type the third number: ");
read = read + (Integer.parseInt(reader.nextLine()));
sum = read;
System.out.println("Sum: " + sum);
由于变量read
被多次声明,因此出现语法错误
您还可以使用:
重新声明变量时,如果再次尝试声明相同的变量,将出现语法错误
int read = Integer.parseInt(reader.nextLine());
System.out.print("Type the second number: ");
read = read + (Integer.parseInt(reader.nextLine()));
System.out.print("Type the third number: ");
read = read + (Integer.parseInt(reader.nextLine()));
重新声明变量时,如果再次尝试声明相同的变量,将出现语法错误
int read = Integer.parseInt(reader.nextLine());
System.out.print("Type the second number: ");
read = read + (Integer.parseInt(reader.nextLine()));
System.out.print("Type the third number: ");
read = read + (Integer.parseInt(reader.nextLine()));
包ejercicio.pkg25.cambio.de.variables.suma.de.tres.numeros /** *@作者迭戈·乌雷亚 */ 导入java.util.Scanner 公共类EJERCICI25CAMBIODEVARIABLESSUMADETRESNUMEROS{
public static void main(String[] args) {
Scanner reader = new Scanner(System.in);
int sum = 0;
int read;
System.out.println("Digita el primer número");
read = Integer.parseInt(reader.nextLine());
sum = sum+read;
System.out.println("Digita el segundo número");
read = Integer.parseInt(reader.nextLine());
sum = sum+read;
System.out.println("Digita el número tres");
read = Integer.parseInt(reader.nextLine());
sum = sum+read;
System.out.println("Sum: " + sum);
}
}包ejercicio.pkg25.cambio.de.variables.suma.de.tres.numeros /** *@作者迭戈·乌雷亚 */ 导入java.util.Scanner 公共类EJERCICI25CAMBIODEVARIABLESSUMADETRESNUMEROS{
public static void main(String[] args) {
Scanner reader = new Scanner(System.in);
int sum = 0;
int read;
System.out.println("Digita el primer número");
read = Integer.parseInt(reader.nextLine());
sum = sum+read;
System.out.println("Digita el segundo número");
read = Integer.parseInt(reader.nextLine());
sum = sum+read;
System.out.println("Digita el número tres");
read = Integer.parseInt(reader.nextLine());
sum = sum+read;
System.out.println("Sum: " + sum);
}
}实际上,对于这个简短的问题,您甚至不需要使用
read
变量
你可以这样做
Scanner reader = new Scanner(System.in);
int sum = 0;
System.out.print("Type the first Number: ");
sum += Integer.parseInt(reader.nextLine());
System.out.print("Type the second number: ");
sum += Integer.parseInt(reader.nextLine());
System.out.print("Type the third number: ");
sum += Integer.parseInt(reader.nextLine());
System.out.println("Sum: " + sum);
输入:
1
2
3
输出:
6
实际上,对于这个简短的问题,甚至不需要使用
read
变量
你可以这样做
Scanner reader = new Scanner(System.in);
int sum = 0;
System.out.print("Type the first Number: ");
sum += Integer.parseInt(reader.nextLine());
System.out.print("Type the second number: ");
sum += Integer.parseInt(reader.nextLine());
System.out.print("Type the third number: ");
sum += Integer.parseInt(reader.nextLine());
System.out.println("Sum: " + sum);
输入:
1
2
3
输出:
6
您不应该一次又一次地声明变量<代码>整数读取仅用于创建变量。之后,您可以使用
读取。另外,最好是将结果累加在sum中而不是read中,这就是它的目的,毕竟你不应该一遍遍地声明变量<代码>整数读取
仅用于创建变量。之后,您可以使用读取。另外,可能最好是将结果累加在sum中,而不是在read中,这就是它的目的。毕竟,也可以使用reader.nextInt()
而不是Integer.parseInt(reader.nextLine())
。也可以使用reader.nextInt()
而不是Integer.parseInt(reader.nextLine())
@user2464795备注:您的错误是由在同一范围内创建同一变量引起的。@user2464795备注:您的错误是由在同一范围内创建同一变量引起的。