Added 229. Majority Element II

Author: LuaanNguyen

medium/229_majority_element_II/229_majority_element_II.go

@@ -0,0 +1,42 @@
+package majority_element_II
+
+func majorityElement(nums []int) []int {
+    count := make(map[int]int)
+
+    for _, n := range nums {
+        count[n]++ 
+
+        if len(count) <= 2 {
+            continue 
+        }
+
+        new_count := make(map[int]int)
+        for k, v := range count {
+            if v > 1 {
+                new_count[k] = v - 1
+            }
+        }
+        count = new_count
+    }
+
+    res := make([]int, 0)
+    seen := make(map[int]bool)
+
+	for k := range count {
+		if seen[k] {
+			continue
+		}
+		occurrence := 0
+		for _, n := range nums {
+			if n == k {
+				occurrence++
+			}
+		}
+		if occurrence > len(nums)/3 {
+	        res = append(res, k)
+		}
+		seen[k] = true
+	}
+
+	return res
+}

medium/229_majority_element_II/229_majority_element_II_test.go

@@ -0,0 +1,39 @@
+package majority_element_II
+
+import (
+	"reflect"
+	"testing"
+)
+
+func MajorityElementTest(t *testing.T) {
+	tests := []struct {
+		name	string
+		nums 	[]int
+		expectedResult []int
+	} {
+		{
+			name: "Test Case 1",
+			nums: []int{3,2,3},
+			expectedResult: []int{3},
+		},
+		{
+			name: "Test Case 2",
+			nums: []int{1},
+			expectedResult: []int{1},
+		},
+		{
+			name: "Test Case 3",
+			nums: []int{1,2},
+			expectedResult: []int{1,2},
+		},
+	}
+
+	for _, test := range tests {
+		t.Run(test.name, func(t * testing.T) {
+			got := majorityElement(test.nums)
+			if !reflect.DeepEqual(got, test.expectedResult) {
+				t.Errorf("majorityElement( %v ) = %v; want = %v", test.nums, got, test.expectedResult)
+			}
+		})
+	}
+}