java-统计字符串中每个字符出现的次数
程序员文章站
2022-04-18 21:26:58
...
import java.util.*;
public class CountMap {
public static void main(String[] args) {
System.out.println("Please input a string: ");
Scanner in = new Scanner(System.in);
String s = in.nextLine();
char[] array = s.toCharArray();
//(key,value)-->(Character,Integer)-->(字符,次数)
Map map = new TreeMap();
for(int i = 0; i<array.length; i++) {
//array[i]相当于key
if(map.containsKey(array[i])) {
Integer value = (Integer)map.get(array[i]);
map.replace(array[i], value+1);
}else {
map.put(array[i], 1);
}
}
Set keys = map.keySet();
Iterator iter = keys.iterator();
Character key;
Integer value;
while(iter.hasNext()) {
key = (Character)iter.next();
value = (Integer)map.get(key);
System.out.println(key + ":" +value);
}
}//end main
}