[英]How can I generate the squares of the digits of an integer
I am trying to write a command line program that accepts inputs.我正在尝试编写一个接受输入的命令行程序。 If the input is an integer , it squares every digit of the number and concatenate them but if the input is not an integer then it asks the user to input a digit.如果输入是 integer ,它会对该数字的每个数字进行平方并将它们连接起来,但如果输入不是整数,则它会要求用户输入一个数字。 But the output is wrong.但是输出是错误的。 Please Check the code.请检查代码。
package com.company;
import java.util.*;
public class ExerciseB {
public static void main (String[] args) {
while (true) {
System.out.println("Enter a digit or 'quit' to quit: ");
Scanner userInput = new Scanner(System.in);
if (userInput.hasNextInt()) {
int intInput = userInput.nextInt();
int i;
int intCharSquare;
ArrayList<Integer> valueCharSquare = new ArrayList<>();
//Generating the square of each character of the inputted integer and adding it to the valueCharSquare ArrayList
String stringOfIntInput= String.valueOf(intInput);
for (i = 0; i <= stringOfIntInput.length() - 1; i++) {
intCharSquare = (int) Math.pow((int) stringOfIntInput.charAt(i),2);
valueCharSquare.add(intCharSquare);
}
// Storing the first value of the valueCharSquare ArrayList into a variable
int result = valueCharSquare.get(0);
//Converting the value of result into a string
String.valueOf(result);
/* Obtaining the other values of the valueCharSquare ArrayList
* and storing them into otherResult variable
* then converting otherResult into a string
* then concatenating the values of result and otherResults
*/
for (i = 1; i <= valueCharSquare.size() - 1; i++) {
int otherResults = valueCharSquare.get(i);
String.valueOf(otherResults);
result = result + otherResults;
}
//printing out new value of result
System.out.println(result);
// This happens if the user input is a string
} else if (userInput.hasNext()) {
String stringInput = userInput.nextLine();
if (stringInput.equals("quit")) {
break;
} else {
continue;
}
}
}
}
} }
You should write a separate method for squaring the digits of an integer, eg something like this:您应该编写一个单独的方法来平方整数的数字,例如这样的:
static String squareDigits(int number) {
String numberString = Integer.toString(number);
StringBuilder buf = new StringBuilder();
if (number < 0)
buf.append('-');
for (int i = (number < 0 ? 1 : 0); i < numberString.length(); i++) {
int digit = Character.digit(numberString.charAt(i), 10);
buf.append(digit * digit);
}
return buf.toString();
}
Then you can test it independently of your user input/output logic:然后您可以独立于您的用户输入/输出逻辑对其进行测试:
System.out.println(squareDigits(13579)); // prints: 19254981
System.out.println(squareDigits(-2468)); // prints: -4163664
System.out.println(squareDigits(0)); // prints: 0
System.out.println(squareDigits(1999999999)); // prints: 1818181818181818181
声明:本站的技术帖子网页,遵循CC BY-SA 4.0协议,如果您需要转载,请注明本站网址或者原文地址。任何问题请咨询:yoyou2525@163.com.