package leetcode // 解法一 时间复杂度 O(n) 空间复杂度 O(1) func majorityElement229(nums []int) []int { // since we are checking if a num appears more than 1/3 of the time // it is only possible to have at most 2 nums (>1/3 + >1/3 = >2/3) count1, count2, candidate1, candidate2 := 0, 0, 0, 1 // Select Candidates for _, num := range nums { if num == candidate1 { count1++ } else if num == candidate2 { count2++ } else if count1 <= 0 { // We have a bad first candidate, replace! candidate1, count1 = num, 1 } else if count2 <= 0 { // We have a bad second candidate, replace! candidate2, count2 = num, 1 } else { // Both candidates suck, boo! count1-- count2-- } } // Recount! count1, count2 = 0, 0 for _, num := range nums { if num == candidate1 { count1++ } else if num == candidate2 { count2++ } } length := len(nums) if count1 > length/3 && count2 > length/3 { return []int{candidate1, candidate2} } if count1 > length/3 { return []int{candidate1} } if count2 > length/3 { return []int{candidate2} } return []int{} } // 解法二 时间复杂度 O(n) 空间复杂度 O(n) func majorityElement229_1(nums []int) []int { result, m := make([]int, 0), make(map[int]int) for _, val := range nums { if v, ok := m[val]; ok { m[val] = v + 1 } else { m[val] = 1 } } for k, v := range m { if v > len(nums)/3 { result = append(result, k) } } return result }