我尝试使用substring方法,但我想继续使用它,我的“ +”工作正常,但我的“-”工作无效。
这里是我的代码:
import java.util.Scanner;
public class Calculator{
public static void main(String[]args){
Scanner keyboard = new Scanner(System.in);
String num = keyboard.next();
for (int x = 0; x < num.length(); x++){
char n = num.charAt(x);
if (n == '+'){
int result = Integer.parseInt(num.substring(0, x)) + Integer.parseInt(num.substring(x, num.length()));
System.out.println(result);
}
}
String num2 = keyboard.next();
for (int x = 0; x < num2.length(); x++){
char n = num2.charAt(x);
if (n == '-'){
int result = Integer.parseInt(num.substring(0, x)) - Integer.parseInt(num.substring(x, num.length()));
System.out.println(result);
}
}
}
}
public static void main(String[] args) {
Scanner keyboard = new Scanner(System.in);
String num = keyboard.next();
for (int x = 0; x < num.length(); x++){
char n = num.charAt(x);
if (n == '+'){
int result = Integer.parseInt(num.substring(0, x)) + Integer.parseInt(num.substring(x, num.length()));
System.out.println(result);
}
else if (n == '-'){
int result = Integer.parseInt(num.substring(0, x)) - Integer.parseInt(num.substring(x+1, num.length()));
System.out.println(result);
}
}
}