using System; using System.Collections.Generic; // https://www.sololearn.com/Discuss/711001/?ref=app namespace SoloLearn { class Program { static Dictionary BRACKET_PAIRS = new Dictionary { { '<', '>' }, { '(', ')' }, { '[', ']' } }; static void Main(string[] zephyr_koo) { int degree; foreach (var pattern in new string[] { "(()<<[]>>)", "<<>>()", "()<>[]", "[[<<(())>>]]", "((<>>[])", "(><)", "(<)>", "))((" }) { Console.WriteLine(IsValidWrapping(pattern, out degree) ? $"Yes! ^_^ { pattern } with degree { degree }" : $"Nope! -_- { pattern }" ); Console.WriteLine(Environment.NewLine); } } static bool IsValidWrapping(string pattern, out int degree) { degree = 0; var stackOfBrackets = new Stack(); foreach (var bracket in pattern) { if (BRACKET_PAIRS.ContainsKey(bracket)) // is open bracket? { stackOfBrackets.Push(bracket); } else if (stackOfBrackets.Count > 0) { var previousBracket = stackOfBrackets.Pop(); if (BRACKET_PAIRS[previousBracket] != bracket) // is bracket match? return false; } else // begin with closing bracket { return false; } degree = Math.Max(degree, stackOfBrackets.Count - 1); // inspired by Zizibee //if (stackOfBrackets.Count > degree) degree = stackOfBrackets.Count - 1; } return stackOfBrackets.Count == 0; } } }

To Wrap or Not To Wrap (this.Challenge)