add sol

leetcode/169.MajorityElement/majorityElement.go

@@ -0,0 +1,45 @@
+// https://leetcode.com/problems/majority-element/
+
+package main
+
+import "fmt"
+
+// Moore Voting Algo
+func majorityElement(nums []int) int {
+	res := 0
+	cnt := 0
+
+	for _, num := range nums {
+		if cnt == 0 {
+			res = num
+		}
+		if num == res {
+			cnt++
+		} else {
+			cnt--
+		}
+	}
+
+	return res
+}
+
+// Hashmap
+func majorityElement1(nums []int) int {
+	n := len(nums)
+	cnt := make(map[int]int)
+
+	for _, num := range nums {
+		cnt[num]++
+
+		if cnt[num] > n/2 {
+			return num
+		}
+	}
+
+	return -1
+}
+
+func main() {
+	nums := []int{2, 2, 2, 1, 1, 1, 2}
+	fmt.Println(majorityElement1(nums))
+}