1957C - How Does the Rook Move - CodeForces Solution

import math

MOD = 1000000007

def find_configs():
    n, k = map(int, input().split())

    row_set = set(range(1, n + 1))
    col_set = set(range(1, n + 1))

    for _ in range(k):
        x, y = map(int, input().split())
        row_set.discard(x)
        col_set.discard(y)
        row_set.discard(y)
        col_set.discard(x)

    ns = len(row_set)
    de = [0] * (ns + 1)
    de[0] = 1

    for i in range(1, ns + 1):
        de[i] = de[i - 1] % MOD
        if i - 2 >= 0:
            er = (i - 1) * de[i - 2] % MOD
            er *= 2
            er %= MOD
            de[i] += er
            de[i] %= MOD

    return de[ns]


    





import os
import sys
from io import BytesIO, IOBase
from collections import Counter
def inmap():
    return map(int,input().split())
def inarr():
    return list(map(int,input().split()))
def main():
   for _ in range(int(input())):
    
        result = find_configs()
        print(result)





BUFSIZE = 8192


class FastIO(IOBase):
    newlines = 0

    def __init__(self, file):
        self._file = file
        self._fd = file.fileno()
        self.buffer = BytesIO()
        self.writable = "x" in file.mode or "r" not in file.mode
        self.write = self.buffer.write if self.writable else None

    def read(self):
        while True:
            b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE))
            if not b:
                break
            ptr = self.buffer.tell()
            self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr)
        self.newlines = 0
        return self.buffer.read()

    def readline(self):
        while self.newlines == 0:
            b = os.read(self._fd, max(os.fstat(self._fd).st_size, BUFSIZE))
            self.newlines = b.count(b"\n") + (not b)
            ptr = self.buffer.tell()
            self.buffer.seek(0, 2), self.buffer.write(b), self.buffer.seek(ptr)
        self.newlines -= 1
        return self.buffer.readline()

    def flush(self):
        if self.writable:
            os.write(self._fd, self.buffer.getvalue())
            self.buffer.truncate(0), self.buffer.seek(0)


class IOWrapper(IOBase):
    def __init__(self, file):
        self.buffer = FastIO(file)
        self.flush = self.buffer.flush
        self.writable = self.buffer.writable
        self.write = lambda s: self.buffer.write(s.encode("ascii"))
        self.read = lambda: self.buffer.read().decode("ascii")
        self.readline = lambda: self.buffer.readline().decode("ascii")


sys.stdin, sys.stdout = IOWrapper(sys.stdin), IOWrapper(sys.stdout)
input = lambda: sys.stdin.readline().rstrip("\r\n")


if __name__ == "__main__":
    main()