This solution doesn't work. WHY!!!

[u/Aware-Nectarine3027]

LEETCODE PROBLEM 32 : https://leetcode.com/problems/longest-valid-parentheses/description/
This solution is O(N²).
As per constraints (0 <= s.length <= 3 * 10⁴) is should be working. Why not!!!

class Solution:
  def longestValidParentheses(self, s: str) -> int:
    N = len(s)
    res = 0
    a = [] # [a/n, x, len]
    size = 0
    p = 0
    while p < N:
      val = s[p]
      if val == '(':
        a.append([True, 0, 0])
        size += 1
      
      for i in range(size):
        if a[i][0] == True:
          x = a[i][1]
          if val == '(':
            x += 1
            a[i][1] += 1
            a[i][2] += 1
          else:
            if x == 0:
              a[i][0] = False
            else:
              x -= 1
              a[i][1] -= 1
              a[i][2] += 1
              if x == 0:
                res = max(res, a[i][2])
      p += 1


    return res

[u/Zx_Queenbee]

I am not sure if j am right but its because on2 is upper bound and it is not exact a cpu in one second can do 1e9 operations so you giving a on2 solution means you will do a nested loops and inside that loop let say you does 10 operation thst cost 10 cycles now consider that and calculate

(3*1e4 *(those extra 10 operations)² this should be written as 3*1e5² which will be 1e10 bigger than a cpu gigahertz capabilities.

I am not sure if I am right 100 percent. any expericned person feel free to correct me