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# Check if expression contains redundant bracket or not | Set 2

• Difficulty Level : Easy
• Last Updated : 08 Jun, 2021

Given a string of balanced expression, find if it contains a redundant parenthesis or not. A set of parenthesis are redundant if the same sub-expression is surrounded by unnecessary or multiple brackets. Print ‘Yes’ if redundant else ‘No’.
Note: Expression may contain ‘+’, ‘*‘, ‘–‘ and ‘/‘ operators. Given expression is valid and there are no white spaces present.
Note: The problem is intended to solve in O(1) extra space.
Examples:

Input: ((a+b))
Output: YES
((a+b)) can reduced to (a+b)
Input: (a+(b)/c)
Output: YES
(a+(b)/c) can reduced to (a+b/c) because b is surrounded by () which is redundant
Input: (a+b*(c-d))
Output: NO
(a+b*(c-d)) doesn’t have any redundant or multiple brackets

Approach:
The idea is very similar to the idea discussed in the previous article but here in place of stack we are counting the symbol ( ‘+’, ‘*‘, ‘–‘ and ‘/‘ ) and the total number of brackets used in the expression.
If the count of brackets is not equal to the count of the symbols then the function will return false.

## C++

 `// C++ program to check for/``// redundant braces in the string``#include ``using` `namespace` `std;` `// Function to check for``// redundant braces``bool` `IsRedundantBraces(string A)``{``    ``// count of no of signs``    ``int` `a = 0, b = 0;``    ``for` `(``int` `i = 0; i < A.size(); i++) {``        ``if` `(A[i] == ``'('``            ``&& A[i + 2] == ``')'``)``            ``return` `1;``        ``if` `(A[i] == ``'*'``            ``|| A[i] == ``'+'``            ``|| A[i] == ``'-'``            ``|| A[i] == ``'/'``)``            ``a++;``        ``if` `(A[i] == ``'('``)``            ``b++;``    ``}``    ``if` `(b > a)``        ``return` `1;``    ``return` `0;``}` `// Driver function``int` `main()``{``    ``string A = ``"(((a+b) + c) + d)"``;``    ``if` `(IsRedundantBraces(A)) {``        ``cout << ``"YES\n"``;``    ``}``    ``else` `{``        ``cout << ``"NO"``;``    ``}``}`

## Java

 `// Java program to check for``// redundant braces in the string``class` `GFG``{``    ` `    ``// Function to check for``    ``// redundant braces``    ``static` `boolean` `IsRedundantBraces(String A)``    ``{``        ``// count of no of signs``        ``int` `a = ``0``, b = ``0``;``        ``for` `(``int` `i = ``0``; i < A.length(); i++)``        ``{``            ``if` `(A.charAt(i) == ``'('` `&&  ``                ``A.charAt(i + ``2``) == ``')'``)``                ``return` `true``;``                ` `            ``if` `(A.charAt(i) == ``'*'` `||``                ``A.charAt(i) == ``'+'` `||``                ``A.charAt(i) == ``'-'` `||``                ``A.charAt(i) == ``'/'``)``                ``a++;``            ``if` `(A.charAt(i) == ``'('``)``                ``b++;``        ``}``        ``if` `(b > a)``            ``return` `true``;``        ``return` `false``;``    ``}``    ` `    ``// Driver Code``    ``public` `static` `void` `main (String[] args)``    ``{``        ``String A = ``"(((a+b) + c) + d)"``;``        ``if` `(IsRedundantBraces(A))``        ``{``            ``System.out.println(``"YES"``);``        ``}``        ``else``        ``{``            ``System.out.println(``"NO"``);``        ``}``    ``}``}` `// This code is contributed by AnkitRai01`

## Python3

 `# Python3 program to check for/``# redundant braces in the string` `# Function to check for``# redundant braces``def` `IsRedundantBraces(A):``    ` `    ``# count of no of signs``    ``a, b ``=` `0``, ``0``;``    ``for` `i ``in` `range``(``len``(A)):``        ``if` `(A[i] ``=``=` `'('` `and` `A[i ``+` `2``] ``=``=` `')'``):``            ``return` `True``;``        ``if` `(A[i] ``=``=` `'*'` `or` `A[i] ``=``=` `'+'` `or``            ``A[i] ``=``=` `'-'` `or` `A[i] ``=``=` `'/'``):``            ``a ``+``=` `1``;``        ``if` `(A[i] ``=``=` `'('``):``            ``b ``+``=` `1``;``    ` `    ``if` `(b > a):``        ``return` `True``;``    ``return` `False``;` `# Driver Code``if` `__name__ ``=``=` `'__main__'``:``    ``A ``=` `"(((a+b) + c) + d)"``;``    ``if` `(IsRedundantBraces(A)):``        ``print``(``"YES"``);``    ` `    ``else``:``        ``print``(``"NO"``);``    ` `# This code is contributed by PrinciRaj1992`

## C#

 `// C# program to check for``// redundant braces in the string``using` `System;``                    ` `class` `GFG``{``    ` `// Function to check for``// redundant braces``static` `bool` `IsRedundantBraces(``string` `A)``{``    ``// count of no of signs``    ``int` `a = 0, b = 0;``    ``for` `(``int` `i = 0; i < A.Length; i++)``    ``{``        ``if` `(A[i] == ``'('` `&& A[i + 2] == ``')'``)``            ``return` `true``;``        ``if` `(A[i] == ``'*'` `|| A[i] == ``'+'` `||``            ``A[i] == ``'-'` `|| A[i] == ``'/'``)``            ``a++;``        ``if` `(A[i] == ``'('``)``            ``b++;``    ``}``    ``if` `(b > a)``        ``return` `true``;``    ``return` `false``;``}``    ` `// Driver Code``public` `static` `void` `Main (String[] args)``{``    ``String A = ``"(((a+b) + c) + d)"``;``    ``if` `(IsRedundantBraces(A))``    ``{``        ``Console.WriteLine(``"YES"``);``    ``}``    ``else``    ``{``        ``Console.WriteLine(``"NO"``);``    ``}``}``}` `// This code is contributed by PrinciRaj1992`

## Javascript

 ``
Output:
`NO`

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