package main
import (
"errors"
"fmt"
)
// findMaxSumOfThree finds 'k' consecutive numbers with the largest sum in a slice.
// It returns the maximum sum, the corresponding subslice of numbers, and an error if invalid.
func findMaxSumOfThree(numbers []int, k int) (int, []int, error) {
// Validate input parameters
if k <= 0 || len(numbers) < k {
return 0, nil, errors.New("slice length is smaller than k or k is invalid")
}
// Compute the sum of the first window of size k
currentSum := 0
for i := 0; i < k; i++ {
currentSum += numbers[i]
}
maxSum := currentSum
maxStartIndex := 0
// Slide the window across the rest of the slice:
// Subtract the element leaving the window on the left, and add the new element on the right.
for i := k; i < len(numbers); i++ {
currentSum = currentSum - numbers[i-k] + numbers[i]
if currentSum > maxSum {
maxSum = currentSum
maxStartIndex = i - k + 1
}
}
// Extract and return the sequence with the maximum sum
resultNumbers := numbers[maxStartIndex : maxStartIndex+k]
return maxSum, resultNumbers, nil
}
func main() {
numbers := []int{4, 2, 0, 8, 7, 5, 1, 3, 9, 6}
k := 3
sum, result, err := findMaxSumOfThree(numbers, k)
if err != nil {
fmt.Printf("Error: %v\n", err)
return
}
fmt.Printf("Largest sum: %d\n", sum)
fmt.Printf("Numbers: %v\n", result)
}
/*
run:
Largest sum: 20
Numbers: [8 7 5]
*/
