计算字符串中的空白量

Question

好的，既然我已将public static String更改为public static int，则最后一项功能无法打印出来。

谢谢大家的帮助。

这是完整的程序。最后一个功能似乎没有打印。

import java.lang.String;
import java.util.Scanner;

public class stringFuncts{

  /**
 * @param <String> <str> <Takes in a String and reverses it.>
 * @return <rev> <returns the reversed string>
 */
  public static String reverseString (String str){
    String rev = "";
    int length = str.length();

    for ( int i = length - 1 ; i >= 0 ; i-- ){
      rev = rev + str.charAt(i);
    }
    return rev;
  }

  /**
 * @param <int> <n> <It will sum up the odds of a set number>
 * @return <results> <Will print out the total of the odds values>
 */
  public static int sumOfOdds (int n){
    int results = 0;

    for(int i = 1; i <= n*2; i += 2){
      results = results + i;
    }

    return results;
  }

  /**
 * @param <int> <blanks> <Will count the amount of whitespace in the phrase>
 * @return <numBlanks> <Will return the amount of whitespace found in the String>
 */
    public static int numberOfBlanks(String blanks){
        int numBlanks = 0;

        for(int i = 0; i < blanks.length(); i++) {
         if(Character.isWhitespace(blanks.charAt(i))) 
            numBlanks++;
        }
        return numBlanks;
    }

  public static void main(String [] args){
    Scanner input = new Scanner(System.in);
    String str;
    int n = 0;
    String blanks;

    System.out.println("Enter a string to reverse");
    str = input.nextLine();
    System.out.println("The reverse output is: " + reverseString(str));

    System.out.println("");

    System.out.println("Enter a value to sum the odds");
    n = input.nextInt();
    System.out.println("The sum of the odds " + sumOfOdds(n));

    System.out.println("");

    System.out.println("Enter a string to find the amount of blanks");
    blanks = input.nextLine();
    System.out.print("The number od blanks in the string is: " + numberOfBlanks(blanks));
  }
}

Answer 1

在numberOfBlanks()返回类型中，String数据类型为int 将其更改为{{1}}数据类型

Answer 2

您的函数声明为public static String。您正在尝试返回一个数字，因此正确的声明将为public static int。

Answer 3

import java.lang.String;
import java.util.Scanner;

public class stringFuncts{

  /**
 * @param <String> <str> <Takes in a String and reverses it.>
 * @return <rev> <returns the reversed string>
 */
  public static String reverseString (String str){
    String rev = "";
    int length = str.length();

    for ( int i = length - 1 ; i >= 0 ; i-- ){
      rev = rev + str.charAt(i);
    }
    return rev;
  }

  /**
 * @param <int> <n> <It will sum up the odds of a set number>
 * @return <results> <Will print out the total of the odds values>
 */
  public static int sumOfOdds (int n){
    int results = 0;

    for(int i = 1; i <= n*2; i += 2){
      results = results + i;
    }

    return results;
  }

  /**
 * @param <int> <blanks> <Will count the amount of whitespace in the phrase>
 * @return <numBlanks> <Will return the amount of whitespace found in the String>
 */
    public static int numberOfBlanks(String blanks){
        int numBlanks = 0;

        for(int i = 0; i < blanks.length(); i++) {
         if(Character.isWhitespace(blanks.charAt(i))) 
            numBlanks++;
        }
        return numBlanks;
    }

  public static void main(String [] args){
    Scanner input = new Scanner(System.in);
    String str;
    int n = 0;
    String blanks;

    System.out.println("Enter a string to reverse");
    str = input.nextLine();
    System.out.println("The reverse output is: " + reverseString(str));

    System.out.println("");

    System.out.println("Enter a value to sum the odds");
    n = input.nextInt();
    System.out.println("The sum of the odds " + sumOfOdds(n));

    System.out.println("");
     input.nextLine();
    System.out.println("Enter a string to find the amount of blanks");
    blanks = input.nextLine();
    System.out.print("The number od blanks in the string is: " + numberOfBlanks(blanks));
  }
}

输出：

Enter a string to reverse
this
The reverse output is: siht

Enter a value to sum the odds
3
The sum of the odds 9

Enter a string to find the amount of blanks
this is spartan!
The number od blanks in the string is: 2