package leetcode

import lib.*
import org.assertj.core.api.Assertions.assertThat
import org.junit.jupiter.params.*
import org.junit.jupiter.params.provider.*

/**
 * https://leetcode.com/problems/maximum-nesting-depth-of-the-parentheses/
 *
 * 1614. Maximum Nesting Depth of the Parentheses
 * [Easy]
 *
 * A string is a valid parentheses string (denoted VPS) if it meets one of the following:
 *
 * It is an empty string "", or a single character not equal to "(" or ")",
 * It can be written as AB (A concatenated with B), where A and B are VPS's, or
 * It can be written as (A), where A is a VPS.
 *
 * We can similarly define the nesting depth depth(S) of any VPS S as follows:
 * - depth("") = 0
 * - depth(C) = 0, where C is a string with a single character not equal to "(" or ")".
 * - depth(A + B) = max(depth(A), depth(B)), where A and B are VPS's.
 * - depth("(" + A + ")") = 1 + depth(A), where A is a VPS.
 *
 * For example, "", "()()", and "()(()())" are VPS's (with nesting depths 0, 1, and 2),
 * and ")(" and "(()" are not VPS's.
 *
 * Given a VPS represented as string s, return the nesting depth of s.
 *
 * Constraints
 * - 1 <= s.length <= 100
 * - s consists of digits 0-9 and characters '+', '-', '*', '/', '(', and ')'.
 * - It is guaranteed that parentheses expression s is a VPS.
 */
fun maxNestingDepth(vps: String) = vps
    .map { when (it) {'(' -> 1; ')' -> -1; else -> 0 } }
    .runningReduce(Int::plus)
    .maxOr { 0 }

/**
 * Unit tests
 */
class NestingDepthOfParenthesesTest {

    @ParameterizedTest
    @CsvSource(
        "1, 0",
        "(1), 1",
        "(1+(2*3)+((8)/4))+1, 3",
        "(1)+((2))+(((3))), 3",
        "1+(2*3)/(2-1), 1"
    )
    fun `max nesting depth of parentheses`(text: String, expectedDepth: Int) {
        assertThat(
            maxNestingDepth(text)
        ).isEqualTo(
            expectedDepth
        )
    }
}