add 137 solution

6boris · 6boris · commit c7500b426014 · 2020-04-03T09:26:23.000+08:00
diff --git a/src/0137.Single-Number-II/Solution.go b/src/0137.Single-Number-II/Solution.go
@@ -1,5 +1,29 @@
 package Solution
 
-func Solution(x bool) bool {
-	return x
+func singleNumber(nums []int) int {
+	m := make(map[int]int, len(nums))
+	for _, v := range nums {
+		m[v]++
+	}
+	for v := range m {
+		if m[v] == 1 {
+			return v
+		}
+	}
+	return 0
+}
+
+//	只循环一次
+// 3 ∗ (a+b+c)−(a+a+b+b+c) = 2 * c
+func singleNumber2(nums []int) int {
+	m := make(map[int]int, len(nums))
+	sum1, sum2 := 0, 0
+	for _, v := range nums {
+		if _, ok := m[v]; !ok {
+			m[v]++
+			sum1 += v
+		}
+		sum2 += v
+	}
+	return (3*sum1 - sum2) / 2
 }
diff --git a/src/0137.Single-Number-II/Solution_test.go b/src/0137.Single-Number-II/Solution_test.go
@@ -10,18 +10,40 @@ func TestSolution(t *testing.T) {
 	//	测试用例
 	cases := []struct {
 		name   string
-		inputs bool
-		expect bool
+		inputs []int
+		expect int
 	}{
-		{"TestCase", true, true},
-		{"TestCase", true, true},
-		{"TestCase", false, false},
+		{"TestCase", []int{2, 2, 3, 2}, 3},
+		{"TestCase", []int{0, 1, 0, 1, 0, 1, 99}, 99},
 	}
 
 	//	开始测试
 	for i, c := range cases {
 		t.Run(c.name+" "+strconv.Itoa(i), func(t *testing.T) {
-			got := Solution(c.inputs)
+			got := singleNumber(c.inputs)
+			if !reflect.DeepEqual(got, c.expect) {
+				t.Fatalf("expected: %v, but got: %v, with inputs: %v",
+					c.expect, got, c.inputs)
+			}
+		})
+	}
+}
+
+func TestSolution2(t *testing.T) {
+	//	测试用例
+	cases := []struct {
+		name   string
+		inputs []int
+		expect int
+	}{
+		{"TestCase", []int{2, 2, 3, 2}, 3},
+		{"TestCase", []int{0, 1, 0, 1, 0, 1, 99}, 99},
+	}
+
+	//	开始测试
+	for i, c := range cases {
+		t.Run(c.name+" "+strconv.Itoa(i), func(t *testing.T) {
+			got := singleNumber2(c.inputs)
 			if !reflect.DeepEqual(got, c.expect) {
 				t.Fatalf("expected: %v, but got: %v, with inputs: %v",
 					c.expect, got, c.inputs)
