java.util.Scanner scanner = new java.util.Scanner(System.in); java.util.Map map = new java.util.HashTbale(); for(int i=0;i<20;i++){ System.out.println("请输入一个10以内的正整数:"); int num = scanner.nextInt(); if(map.containsKey(num)){ map.put(num,map.get(num) + 1); }else{ map.put(num,1); } } for(Integer key : map.keySet()){ System.out.println("数字:"+key +",共出现:"+map.get(key) +"次。"); }