import java.util.Scanner;
//声明变量
public class ISBNChecker {
public static void main(String [] args) {
Scanner keyboard = new Scanner(System.in);
System.out.println("Please enter a 13 digit book number:");
String book = keyboard.nextLine();
int isbn = Integer.parseInt(book);
//检查ISBN号的长度
if (book.length() != 13) {
System.out.println("ILLEGAL ISBN NUMBER");
}
//检查数字是否每1、3、5、7、9、11和13乘以3,其他数字乘以1,然后将它们加在一起
for(int i = 0; i < book.length(); i++){
char c = book.charAt(i); //get the current char
int value = c - '0'; //subtract '0' from the char
isbn += value * (i+1);
//the rest is to see if total of isbn is dividable by 10 to have no remains
}
if ((isbn % 10) != 0) {
System.out.println("Illegal ISBN number");
} else {
System.out.println("It's an ISBN number");
}
}
}
//the problem with this code is that it won't work and I am pretty sure I messed up the format. Please help me check.
// when I process it. this error shows up :
Exception in thread "main" java.lang.NumberFormatException: For input string: "1234567898765"
at java.lang.NumberFormatException.forInputString(NumberFormatException.java:65)
at java.lang.Integer.parseInt(Integer.java:583)
at java.lang.Integer.parseInt(Integer.java:615)
at ISBNChecker.main(ISBNChecker.java:8)
最佳答案
该数字太大,无法容纳整数。尝试改用Long
。
Max Integer is 2147483647.
Max Long is 9223372036854775807L.
关于java - 我的isbn检查器有什么错误?,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/34248057/