In a N x N grid composed of 1 x 1 squares, each 1 x 1 square consists of a /, \, or blank space.  These characters divide the square into contiguous regions.
(Note that backslash characters are escaped, so a \ is represented as "\\".)
Return the number of regions.
 













Example 1:
Input:
[
  " /",
  "/ "
]
Output: 2
Explanation: The 2x2 grid is as follows:



Example 2:
Input:
[
  " /",
  "  "
]
Output: 1
Explanation: The 2x2 grid is as follows:



Example 3:
Input:
[
  "\\/",
  "/\\"
]
Output: 4
Explanation: (Recall that because \ characters are escaped, "\\/" refers to \/, and "/\\" refers to /\.)
The 2x2 grid is as follows:



Example 4:
Input:
[
  "/\\",
  "\\/"
]
Output: 5
Explanation: (Recall that because \ characters are escaped, "/\\" refers to /\, and "\\/" refers to \/.)
The 2x2 grid is as follows:



Example 5:
Input:
[
  "//",
  "/ "
]
Output: 3
Explanation: The 2x2 grid is as follows:


 
Note:

1 <= grid.length == grid[0].length <= 30
grid[i][j] is either '/', '\', or ' '.

```python

USER_FILENAME = "<user_code>"
import sys, json, builtins
import math, heapq, bisect, itertools, functools, collections, statistics, fractions, decimal, operator, array, random, re, string, os, pathlib
try:
    import resource as _res
except Exception:
    _res = None
from collections import Counter, defaultdict, deque, OrderedDict
from functools import lru_cache, reduce
from itertools import accumulate, permutations, combinations, product
from math import gcd, ceil, floor, sqrt
from decimal import Decimal
try:
    from typing import *
except Exception:
    pass
try:
    sys.setrecursionlimit(1_000_000)
except Exception:
    pass
try:
    import site as _site
    try:
        _sys_sites = _site.getsitepackages() if hasattr(_site, "getsitepackages") else []
        for _p in _sys_sites:
            if _p and _p not in sys.path:
                sys.path.append(_p)
    except Exception:
        pass
    try:
        _usp = _site.getusersitepackages()
        if isinstance(_usp, str):
            _usp = [_usp]
        for _p in _usp:
            if _p and _p not in sys.path:
                sys.path.append(_p)
    except Exception:
        pass
except Exception:
    pass

def _disabled_input(*args, **kwargs):
    raise RuntimeError("input() is disabled in callable mode")
builtins.input = _disabled_input

ns = {"__name__": "__judge__"}  # prevent if __name__ == "__main__" blocks
for _k, _v in list(globals().items()):
    if not _k.startswith("_"):
        ns[_k] = _v
_CODE = "class Solution:\n    \n    def regionsBySlashes(self, grid: List[str]):\n        def minAnglePoint(p1, p2, options):\n            minAngle = 10.0     # a ridiculously big number\n            for p3 in options:\n                a = (p2[0] - p1[0], p2[1] - p1[1])\n                b = (p3[0] - p2[0], p3[1] - p2[1])\n                dot = a[0] * b[0] + a[1] * b[1]\n                det = a[0] * b[1] - a[1] * b[0]\n                ang = math.atan2(det, dot)\n                if ang < minAngle: \n                    minAngle = ang\n                    res = p3\n            return res, minAngle\n\n        N = len(grid)\n        M = dict()\n        for i in range(N):\n            M[(i + 1, 0)] = [(i, 0)]\n            M[(N, i + 1)] = [(N, i)]\n            M[(N - i - 1, N)] = [(N - i, N)]\n            M[(0, N - i - 1)] = [(0, N - i)]\n        for y in range(N):\n            x = 0\n            for c in grid[y]:\n                if c == '/':\n                    if (x + 1, y) in M: \n                        M[(x + 1, y)].append((x, y + 1))\n                    else: \n                        M[(x + 1, y)] = [(x, y + 1)]\n                    if (x, y + 1) in M:\n                        M[(x, y + 1)].append((x + 1, y))\n                    else:\n                        M[(x, y + 1)] = [(x + 1, y)]\n                elif c == '\\\\\\\\':\n                    if (x, y) in M: \n                        M[(x, y)].append((x + 1, y + 1))\n                    else:\n                        M[(x, y)] = [(x + 1, y + 1)]\n                    if (x + 1, y + 1) in M: \n                        M[(x + 1, y + 1)].append((x, y))\n                    else:\n                        M[(x + 1, y + 1)] = [(x, y)]\n                x += 1\n        innerangle = round(-2 * math.pi, 4)\n        points = sorted(M)\n        regions = set()\n        for i in range(len(points)):\n            if points[i] not in M: continue\n            startpoint = points[i]\n            region = {startpoint}\n            point = firststep = M[startpoint][0]\n            M[startpoint].remove(point)\n            prev = startpoint\n            angSum = 0\n            while point != startpoint:\n                region.add(point)\n                links = M[point]\n                nxt, ang = minAnglePoint(prev, point, links)\n                angSum += ang\n                if len(links) == 1: \n                    del M[point]\n                else:\n                    M[point].remove(nxt)\n                prev = point\n                point = nxt\n            if len(M[startpoint]) == 0: \n                del M[startpoint]\n            \n            _, ang = minAnglePoint(prev, point, [firststep])\n            angSum = round(angSum + ang, 4)\n            if angSum == innerangle: # it is a valid region\n                regions.add(frozenset(region))\n        return len(regions)"
_co = compile(_CODE, USER_FILENAME, "exec")
exec(_co, ns, ns)

_target = None
_fn_name = 'regionsBySlashes'
if _fn_name:
    if "Solution" in ns:
        try:
            _obj = ns["Solution"]()
            if hasattr(_obj, _fn_name):
                _target = getattr(_obj, _fn_name)
        except Exception:
            _target = None
    if _target is None and _fn_name in ns and callable(ns[_fn_name]):
        _target = ns[_fn_name]
# Fallback: if there's exactly one user-defined function, use it
if _target is None:
    _cands = [v for k, v in ns.items() if callable(v) and getattr(v, "__module__", "") in ("__judge__", "__main__")]
    _user_funcs = [c for c in _cands if getattr(c, "__name__", "").startswith("_") is False]
    if len(_user_funcs) == 1:
        _target = _user_funcs[0]
if _target is None:
    raise RuntimeError(f"Could not resolve callable '{_fn_name}'")

_raw = sys.stdin.read().strip()
if _raw:
    _parsed = json.loads(_raw)
    if isinstance(_parsed, dict):
        _kwargs = _parsed.get("kwargs", {})
        _args = _parsed.get("args", [])
    else:
        _args, _kwargs = _parsed, {}
else:
    _args, _kwargs = [], {}
if not isinstance(_args, (list, tuple)):
    _args = [_args]
_res = _target(*_args, **_kwargs)
try:
    sys.stdout.write(repr(_res) + "\n")
except Exception:
    pass

```

Measured memory_bytes: 11176