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How to find a suitable pair of curly braces in a string?

Suppose I have the line "(paid) + (8 business hours) + (company rules)." Now I want to check if this complete line is enclosed in parentheses or not. Basically, I want to check whether the line is like this or not: "((paid) + (8 business hours) + (company rules))." If it is already enclosed in parentheses, I will leave it as it is, otherwise I will apply parentheses to the complete line so that the result is: "((paid) + (8 business hours) + (company rules))" Counting the number brackets, I could not solve this problem.

Can someone suggest a solution?

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6 answers

Stack - , , , Stack, , , , 0, , , , . , .

:

String s = "((paid for) + (8 working hours) + (company rules))";
var stack = new Stack<int>();
bool isSurroundedByParens = false;
for (int i = 0; i < s.Length; i++) {
    switch (s[i]) {
    case '(':
        stack.Push(i);
        isSurroundedByParens = false;
        break;
    case ')':
        int index = stack.Any() ? stack.Pop() : -1;
        isSurroundedByParens = (index == 0);
        break;
    default:
        isSurroundedByParens = false;
        break;
    }
}
if (!isSurroundedByParens) {
    // surround with parens
}
+10

. , u ( ) . , , ... , .

, ,

: :

() + (8 ) + ( )

( , ), , , , , . , , .

:

(() + (8 ) + ( ))

).

, ...

+2

static void Main()
{
    Console.WriteLine("Expected: {0}, Is: {1}", false, IsSurrounded(""));
    Console.WriteLine("Expected: {0}, Is: {1}", false, IsSurrounded("("));
    Console.WriteLine("Expected: {0}, Is: {1}", false, IsSurrounded(")"));
    Console.WriteLine("Expected: {0}, Is: {1}", true, IsSurrounded("()"));
    Console.WriteLine("Expected: {0}, Is: {1}", false, IsSurrounded("(()"));
    Console.WriteLine("Expected: {0}, Is: {1}", false, IsSurrounded("())"));
    Console.WriteLine("Expected: {0}, Is: {1}", true, IsSurrounded("(.(..)..(..)..)"));
    Console.WriteLine("Expected: {0}, Is: {1}", false, IsSurrounded("(..)..(..)"));
    Console.WriteLine("Expected: {0}, Is: {1}", false, IsSurrounded("(..)..(..)..)"));
    Console.WriteLine("Expected: {0}, Is: {1}", false, IsSurrounded("(.(..)..(..)"));
}

, . .

static bool IsSurrounded(string text)
{
    if (text.Length < 2 || text.First() != '(' || text.Last() != ')')
        return false;

    for (var i = 1; i < text.Length - 1; i++)
    {
        if (text[i] == ')')
            return false;

        if (text[i] == '(')
            break;
    }

    for (var i = text.Length - 2; i > 0; i--)
    {
        if (text[i] == '(')
            return false;

        if (text[i] == ')')
            break;
    }

    return true;
}

, , ((..)) + ((..))

+1

, :

text = "(" + text + ")"

Botz3000:

string text = "(paid for)";

Stack<int> parenthesis = new Stack<int>();
int last = 0;

for (int i = 0; i < text.Length; i++)
{
    if (text[i] == '(')
        parenthesis.Push(i);
    else if (text[i] == ')')
    {
        last = parenthesis.Pop();
    }
}

if (last == 0)
{
    // The matching parenthesis was the first letter.
}
0
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You can check the correct number of brackets using something like a stack. Count for each opening and countdown for each closing parenthesis. The same number of opening and closing brackets means that it matches. If you ever encounter a closing bracket when your score is zero, this is a mismatch. If you want to know if your line was completely covered by parameters, check if they all match, and then check if your line starts with one.

static void BraceMatch(string text)
{
  int level = 0;

  foreach (char c in text)
  {
    if (c == '(')
    {
      // opening brace detected
      level++;
    }

    if (c == ')')
    {
      level--;

      if (level < 0)
      {
        // closing brace detected, without a corresponding opening brace
        throw new ApplicationException("Opening brace missing.");
      }
    }
  }

  if (level > 0)
  {
    // more open than closing braces
    throw new ApplicationException("Closing brace missing.");
  }
}
0
source

Finds the closing parenthesis index

public int FindClosingBracketIndex(string text, char openedBracket = '{', char closedBracket = '}')
{
            int index = text.IndexOf(openedBracket);
            int bracketCount = 1;
            var textArray = text.ToCharArray();

            for (int i = index + 1; i < textArray.Length; i++)
            {
                if (textArray[i] == openedBracket)
                {
                    bracketCount++;
                }
                else if (textArray[i] == closedBracket)
                {
                    bracketCount--;
                }

                if (bracketCount == 0)
                {
                    index = i;
                    break;
                }
            }

            return index;
}
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