如何找出数组中重复次数最多的元素？

数据结构与算法

[TOC

1.空间换时间

但是基本不这样考虑，因为不知道给出的数具体有多大，。，。假如是1000000000，。，

2.map映射应该最直白的了

public class Solution {
    public int findMostFrequenceyInArray(int[] nums) {
        if (nums == null || nums.length == 0) {
            return 0;
        }
        Map<Integer, Integer> map = new HashMap<>();
        for (int i = 0; i < nums.length; i++) {
            Set<Integer> keySet = map.keySet();
            if (!keySet.contains(nums[i])) {
                map.put(nums[i], 1);
            } else {
                map.put(nums[i], map.get(nums[i]) + 1);
            }
        }
        //遍历map，之前不怎么用
        Iterator iterator = map.entrySet().iterator();
        int max = 0;
        int result = 0;
        while (iterator.hasNext()) {
            Map.Entry entry = (Map.Entry) iterator.next();
            int key = (int) entry.getKey();
            int value = (int) entry.getValue();
            System.out.println("key: " + key + "  " + "value: " + value);
            if (value > max) {
                max = value;
                result = key;
            }
        }
        return result;
    }
    public static void main(String[] args) {
        Solution solution = new Solution();
        int[] nums = {1, 1, 1, 2, 3, 3, 3, 3, 3, 4, 4};
        System.out.println(solution.findMostFrequenceyInArray(nums));
    }
}