Java面试题:请统计出"hjhkknmkloi"中出现次数最多的字母及次数
package com.test;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
public class Test {
public static void getMax(){
long start=System.currentTimeMillis();
String str= "hjhkknmkloi";
Map<String,Integer> map=new HashMap<String,Integer>();
for(int i=0;i<str.length();i++){
if(map.containsKey(str.substring(i, i+1))){
int value=map.get(str.substring(i, i+1));
map.put(str.substring(i, i+1),value+1);
}else{
map.put(str.substring(i, i+1),1);
}
}
List<Map.Entry<String,Integer>> list=new ArrayList<Map.Entry<String,Integer>>(map.entrySet());
Collections.reverse(list);
for(Map.Entry<String, Integer> mapping:list){
System.out.println(mapping.getKey()+"----------"+mapping.getValue());
}
long end=System.currentTimeMillis();
System.out.println("耗时:"+(end-start)+"毫秒");
}
public static void main(String[] args) {
Test.getMax();
}
}