# Minimum Bracket Addition - Amazon Top Interview Questions

### Problem Statement :

```Given a string s containing brackets ( and ), return the minimum number of brackets that can be inserted so that the brackets are balanced.

Constraints

n ≤ 100,000 where n is the length of s

Example 1

Input

s = ")))(("

Output

5

Explanation

We can insert ((( to the front and )) to the end```

### Solution :

```                        ```Solution in C++ :

int solve(string s) {
int left = 0;
int stack = 0;

for (auto c : s) {
if (!stack && c == ')')
++left;
else if (c == '(')
++stack;
else
--stack;
}
return left + stack;
}```
```

```                        ```Solution in Java :

import java.util.*;

class Solution {
public int solve(String s) {
int open = 0;
int count = 0;

for (char c : s.toCharArray()) {
if (c == '(')
open++;
else {
if (open == 0)
count++;
else
open--;
}
}
return count + open;
}
}```
```

```                        ```Solution in Python :

class Solution:
def solve(self, s):
stack = []
res = 0

for b in s:
if b == ")":
if len(stack) > 0 and stack[-1] == "(":
stack.pop()
else:
stack.append(")")
else:
stack.append("(")

return len(stack)```
```

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## Balanced Brackets

A bracket is considered to be any one of the following characters: (, ), {, }, [, or ]. Two brackets are considered to be a matched pair if the an opening bracket (i.e., (, [, or {) occurs to the left of a closing bracket (i.e., ), ], or }) of the exact same type. There are three types of matched pairs of brackets: [], {}, and (). A matching pair of brackets is not balanced if the set of bra

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