package solutions func IsSorted(f func(int, int) int, arr []int) bool { ascendingOrdered := true descendingOrdered := true for i := 1; i < len(arr); i++ { if !(f(arr[i-1], arr[i]) >= 0) { ascendingOrdered = false } } for i := 1; i < len(arr); i++ { if !(f(arr[i-1], arr[i]) <= 0) { descendingOrdered = false } } return ascendingOrdered || descendingOrdered }