map统计字符出现次数

package accounting;

import java.util.HashMap;
import java.util.Scanner;
import java.util.Set;

public class CountLettersNumbers {
    
    

	public static void main(String[] args) {
    
    
		Scanner sc = new Scanner(System.in);
		System.out.print("请输入一串字符：");
		String sentence = sc.next();
		HashMap<Character, Integer> map = new HashMap<Character, Integer>();
		for (int i = 1; i < sentence.length(); i++) {
    
    
			char ch = sentence.charAt(i);
			if (map.containsKey(ch)) {
    
    
				int count = map.get(ch);
				count = count + 1;
				map.put(ch, count);
			} else {
    
    
				map.put(ch, 1);
			}
		}
		Set<Character> keySet = map.keySet();
		for (Character chars : keySet) {
    
    
			System.out.println("字符" + chars + ",出现的次数为：" + map.get(chars));
		}

	}

}