题解 | #统计字符串中字母出现次数#

import java.util.Scanner; import java.util.Collection; import java.util.ArrayList; import java.util.Collections;

public class Main { public static void main(String[] args) { String string = "H e l l o ! n o w c o d e r"; Scanner scanner= new Scanner(System.in); String word = scanner.next(); scanner.close(); System.out.println(check(string, word)); }

public static int check(String str, String word) {

    //write your code here......
    Collection<Character> list = new ArrayList<>();
    for(int i = 0;i < str.length();i++){
        list.add(str.charAt(i));
    }
    return Collections.frequency(list,word.charAt(0));

}

}