# Balanced Brackets Sequel - Amazon Top Interview Questions

### Problem Statement :

```Given a string s containing round, curly, and square open and closing brackets, return whether the brackets are balanced.

Constraints

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

Example 1

Input

s = "[(])"

Output

False

Example 2

Input

s = "([])[]({})"

Output

True```

### Solution :

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

bool solve(string s) {
stack<char> stack;

for (char c : s) {
if (c == '(' || c == '{' || c == '[')
stack.push(c);
else {
if (stack.empty())
return false;
else if (c == ')' && stack.top() != '(')
return false;
else if (c == '}' && stack.top() != '{')
return false;
else if (c == ']' && stack.top() != '[')
return false;
else
stack.pop();
}
}

return stack.empty();
}```
```

```                        ```Solution in Python :

class Solution:
def solve(self, s):
# The stack to keep track of opening brackets.
stack = []

# Hash map for keeping track of mappings. This keeps the code very clean.
# Also makes adding more types of parenthesis easier
mapping = {")": "(", "}": "{", "]": "["}

for char in s:
# if char is a closing bracket
if char in mapping:
# Pop the top most element else #, the top most element must be an opening bracket
# of the same type
top = stack.pop() if stack else "#"

if mapping[char] != top:
return False
else:
stack.append(char)

# if the stack is empty, we have a valid expression
# the stack wont be empty for cases like (()
return not stack```
```

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