题解 | #判断学生成绩#

import java.util.*;

public class Main {

public static void main(String[] args) {
    Scanner scanner = new Scanner(System.in);
    String line = scanner.nextLine();
    Map<Character, Integer> map = new LinkedHashMap<Character, Integer>();

    //write your code here......
    // 65 ~ 90   97 ~ 122
    char[] chars = line.toCharArray();
    boolean[] booleans = new boolean[ 122 ];
    for (int i = 0; i < chars.length; i++) {
        if ( (chars[i] >= 65 && chars[i] <= 90) || (chars[i] >= 97 && chars[i] <= 122) ) {
            if ( booleans[chars[i]] ){
                map.put(chars[i], map.get(chars[i]) + 1);
            }else {
                booleans[chars[i]] = true;
                map.put(chars[i],1);
            }
        }
    }

    Set<Map.Entry<Character, Integer>> entrys = map.entrySet();
    for (Map.Entry<Character, Integer> entry : entrys) {
        System.out.println(entry.getKey() + ":" + entry.getValue());
    }
}

}