Add: Maximum Average Subarray I

problems/maximum-average-subarray-i/maximum_average_subarray_i.go

@@ -1 +1,17 @@
 package maximum_average_subarray_i
+
+func findMaxAverage(nums []int, k int) float64 {
+	max, sum := 0, 0
+	for i, v := range nums {
+		sum += v
+		if i == k-1 {
+			max = sum
+		} else if i >= k {
+			sum -= nums[i-k]
+		}
+		if sum > max {
+			max = sum
+		}
+	}
+	return float64(max) / float64(k)
+}

problems/maximum-average-subarray-i/maximum_average_subarray_i_test.go

@@ -1 +1,25 @@
 package maximum_average_subarray_i
+
+import "testing"
+
+type caseType struct {
+	nums     []int
+	k        int
+	expected float64
+}
+
+func TestFindMaxAverage(t *testing.T) {
+	tests := [...]caseType{
+		{
+			nums:     []int{1, 12, -5, -6, 50, 3},
+			k:        4,
+			expected: 12.75,
+		},
+	}
+	for _, tc := range tests {
+		output := findMaxAverage(tc.nums, tc.k)
+		if output != tc.expected {
+			t.Fatalf("input: %v %v, output: %v, expected: %v", tc.nums, tc.k, output, tc.expected)
+		}
+	}
+}