java - 仅计算字母字符

Question

这是我的代码，用于查找第一个非重复字符并返回其索引和字符。我怎样才能让它只计算字母字符？

感谢您的帮助:)

//Java程序查找第一个非重复字符

import java.util.*;
public class GFG 
{ 
    static final int NO_OF_CHARS = 256; 
    static char count[] = new char[NO_OF_CHARS]; 

    /* calculate count of characters 
    in the passed string */
    static void getCharCountArray(String str) 
    { 
        for (int i = 0; i < str.length(); i++) 
            count[str.charAt(i)]++; 
    } 

    /* The method returns index of first non-repeating 
    character in a string. If all characters are repeating 
    then returns -1 */
    static int firstNonRepeating(String str) 
    { 
        getCharCountArray(str); 
        int index = -1, i; 

        for (i = 0; i < str.length(); i++) 
        { 
            if (count[str.charAt(i)] == 1) 
            { 
                index = i; 
                break; 
            } 
        } 

    return index; 
    } 

    // Driver method 
    public static void main (String[] args) 
    { 
        Scanner sc = new Scanner(System.in);
        String str = sc.nextLine();
        int index = firstNonRepeating(str); 

        System.out.println(index == -1 ? "Either all characters are repeating or string " + 
                "is empty" : "First non-repeating character is " + str.charAt(index)); 
                System.out.println(index);
    } 
} 

Answer 1

使用您当前的代码，您所需要的只是:完成后，只需打印字符及其计数即可。如果 isAlphabetic 不是您想要的，则 Character 类还有其他方法来选择字符类型。

String str = sc.nextLine();
for (char c : str.toCharArray()) {
      if (Character.isAlphabetic(c)) {
              count[c]++;
      }
}