我是Java中的新手编码器,我正在尝试在java中创建这个计算器,用户可以在其中输入两个数字并选择要对这些数字执行的操作。但是,当代码选择运算符时,它会跳过用户输入和if语句并直接实现else语句。
import java.util.Scanner;
public class Calculator {
public static void main(String[] args) {
Scanner Calc = new Scanner(System.in);
int n1;
int n2;
int Answer;
System.out.println("Enter the first number: ");
n1 = Calc.nextInt();
System.out.println("Enter the second number:" );
n2 = Calc.nextInt();
System.out.println("Select the order of operation: ");
char operator = Calc.nextLine().charAt(0);
if (operator == '+') {
Answer = (n1 + n2);
System.out.println("Answer:" + Answer);
}
if (operator == '-') {
Answer = (n1 - n2);
System.out.println("Answer:" + Answer);
}
if (operator == '*') {
Answer = (n1 * n2);
System.out.println("Answer:" + Answer);
}
if (operator == '/') {
Answer = (n1/n2);
System.out.println("Answer:" + Answer);
}
else {
System.out.println("not implemented yet. Sorry!");
}
}
}
答案 0 :(得分:1)
在Calc.nextLine();
之后添加n2 = Calc.nextInt();
以使用换行符。
您也没有使用else if
,因此即使之前的if
已经匹配,也会检查所有这些if
条件(导致您的最终其他条件执行只要运算符不'/'
1}})。
在这种情况下,您应该只使用switch
块。
答案 1 :(得分:0)
我对代码进行了一些更改,这应该适用于您,但我也建议使用开关。
Scanner Input = new Scanner(System.in);
try {
System.out.print("Enter a number: ");
int num1 = Input.nextInt();
System.out.print("Enter an operator: ");
char operator = Input.next().charAt(0);
System.out.print("Enter a second number: ");
int num2 = Input.nextInt();
// this part of decision, it doesn't work.
if ('+' == operator) {
System.out.println("Your result is " + (num1 + num2));
} else if ('-' == operator) {
System.out.println("Your result is " + (num1 - num2));
} else if ('*' == operator) {
System.out.println("Your result is " + (num1 * num2));
} else if ('/' == operator) {
System.out.println("Your result is " + (num1 / num2));
}else {
System.out.println("Your answer is not valid");
}
} catch (InputMismatchException e) {
System.out.println("similar to try and except in Python");
}