java - 如何存储字符串的不同字符

Question

public class NoDuplicate { 
    static final int NO_OF_CHARS = 256; 
       
    /* Print duplicates present in the passed string */
    static void printDistinct(String str) 
    { 
        // Create an array of size 256 and count of 
        // every character in it 
        int[] count = new int[NO_OF_CHARS]; 
       
        /* Count array with frequency of characters */
        int i; 
        for (i = 0; i < str.length(); i++) 
            if(str.charAt(i)!=' ') 
                count[(int)str.charAt(i)]++; 
        int n = i; 
       
        // Print characters having count more than 0 
        for (i = 0; i < n; i++) 
            if (count[(int)str.charAt(i)] == 1) 
                System.out.print(str.charAt(i)); 
    } 
       
    /* Driver program*/
    public static void main(String args[]) 
    { 
        String str = "SHINCHAN"; 
        printDistinct(str); 
    } 
} 

我正在尝试将不同的字符存储在字符串中。问题是我的代码删除了所有重复的元素。示例:

Input: SHINCHAN

Actual output: SICA

Desired output: SHINCA (I want to store each element once)

Answer 1

您可以使用 LinkedHashSet 来实现相同的功能:

static void printDistinct(String str) {
    Set<Character> origSet = new LinkedHashSet<Character>();
    StringBuilder concat = new StringBuilder();
    for (int i = 0; i < str.length(); i++) {
        if (origSet.add(str.charAt(i))) {
            concat.append(str.charAt(i));
        }
    }
    System.out.println(concat);
}

<小时/>

如果您使用的是 java-8，您可以这样做:

str.chars().mapToObj(e -> Character.toString((char) e))
           .distinct()
           .forEach(System.out::println);