輸入一個字符串,輸出該字符串由那些字符組成,每個字符出現幾次?
import java.util.HashMap;
import java.util.Map;
import java.util.Scanner;
class t {
public static void main(String[] args) {
Scanner input = new Scanner(System.in);
System.out.print("輸入字符串:");
String s = input.next();
Map<Character, Integer> map = new HashMap<Character, Integer>();
for (int i = 0; i < s.length(); i++) {
Character c = s.charAt(i);
Integer counter = map.get(c);
if (map.containsKey(c)) {
System.out.println("字的個數加一,counter:" + counter);
map.put(c, counter += 1);
} else {
System.out.println("新加一個字符");
map.put(c, 1);
}
}
System.out.println(map);
}
}