BraketsSequence.fs

let isCorrectBracketsSeq (str: string) =
    let getNewBalance balance char =
        if balance < 0 then
            balance
        else
            balance + match char with
                        | '(' -> 1
                        | ')' -> -1
                        | _ -> 0
    
    List.fold getNewBalance 0 (Seq.toList str) = 0

[<EntryPoint>]
let main argv =
    printfn "%b" (isCorrectBracketsSeq "((()))") // true
    printfn "%b" (isCorrectBracketsSeq "qwerty(((())))((7 + 8))(((()))()())") // true
    printfn "%b" (isCorrectBracketsSeq "(()))") // false
    printfn "%b" (isCorrectBracketsSeq ")))(((") // false
    printfn "%b" (isCorrectBracketsSeq "))()(") // false
    0

BraketsSequence.kt

fun main() {
    println("2 * (3(5 -8))(10 - 7)(-(8 + (34) - 9) + 6)".isCorrectBracketsSeq())
    println(")(".isCorrectBracketsSeq())
    println("(()(".isCorrectBracketsSeq())
}

fun String.isCorrectBracketsSeq(): Boolean {
    return 0 == this.fold(0) { balance, it ->
        if (balance < 0) return false
        balance + when (it) {
            '(' -> 1
            ')' -> -1
            else -> 0
        }
    }
}