We split the path by / and use a stack to process each component.

1. Split the string by /.
2. Iterate through components:
   • If component is ..: pop from stack if stack is not empty (go up).
   • If component is . or empty: do nothing.
   • Else: push the component onto the stack.
3. Join the stack elements with / and prepend /.

• Time Complexity: O(N).
• Space Complexity: O(N).

def simplify_path(path):
    stack = []
    components = path.split("/")
    
    for c in components:
        if c == "..":
            if stack:
                stack.pop()
        elif c == "." or not c:
            continue
        else:
            stack.append(c)
            
    return "/" + "/".join(stack)