add 202 solution

Author: 6boris

src/0202.Happy-Number/Solution.go

@@ -1,5 +1,35 @@
 package Solution
 
-func Solution(x bool) bool {
-	return x
+//	快慢指针
+func isHappy(n int) bool {
+	slow, fast := n, squareSum(n)
+	for fast != 1 && slow != fast {
+		slow = squareSum(slow)
+		fast = squareSum(squareSum(fast))
+	}
+	return fast == 1
+}
+
+//	利用 map 判断
+func isHappy2(n int) bool {
+	seen := make(map[int]int)
+	for {
+		if _, ok := seen[n]; ok {
+			return true
+		}
+		seen[n] = -1
+		n = squareSum(n)
+		if n == 1 {
+			return true
+		}
+	}
+}
+
+func squareSum(m int) int {
+	sum := 0
+	for m != 0 {
+		sum += (m % 10) * (m % 10)
+		m /= 10
+	}
+	return sum
 }

src/0202.Happy-Number/Solution_test.go

@@ -10,18 +10,38 @@ func TestSolution(t *testing.T) {
 	//	测试用例
 	cases := []struct {
 		name   string
-		inputs bool
+		inputs int
 		expect bool
 	}{
-		{"TestCase", true, true},
-		{"TestCase", true, true},
-		{"TestCase", false, false},
+		{"TestCase", 19, true},
 	}
 
 	//	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 := isHappy(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 bool
+	}{
+		{"TestCase", 19, true},
+	}
+
+	//	开始测试
+	for i, c := range cases {
+		t.Run(c.name+" "+strconv.Itoa(i), func(t *testing.T) {
+			got := isHappy2(c.inputs)
 			if !reflect.DeepEqual(got, c.expect) {
 				t.Fatalf("expected: %v, but got: %v, with inputs: %v",
 					c.expect, got, c.inputs)