Determine if a Cell Is Reachable at a Given Time — Python

# Time:  O(1)
# Space: O(1)

# constructive algorithms, math
class Solution(object):
    def isReachableAtTime(self, sx, sy, fx, fy, t):
        """
        :type sx: int
        :type sy: int
        :type fx: int
        :type fy: int
        :type t: int
        :rtype: bool
        """
        diff1, diff2 = abs(sx-fx), abs(sy-fy)
        mn = min(diff1, diff2)+abs(diff1-diff2)
        return t >= mn if mn else t != 1