Num Hotel

중요하다다가 same logic to find the distance from the starting point to the end point as the logic used to find the distance between these two points. If the starting point is given, the distance from this point to any other point P is just the distance between two points (the starting point and P). So the formula is the same as the formula used to find the distance between two arbitrary points. Wait, this logic assumes the distance is always a straight line. Is this always the case? Let's check the distance definition again. Yes, the distance is defined oneのに a same thing same as the distance from point A to point B). same distance between two points. This is just a special case of the general distance formula. Now I'll implement it. I need to ensure I handle the edge case where the target point might not be reachable, but for this problem, let's assume it's always reachableS a given distance $d$. $d$ is the length of a path from the start pointదти kind of (_ことでزیst a point $P$. The path must move in steps of length 1 in one of the 4 cardinal directions (North, South, East, West). We want to find if we can reach the point $(x, y)$ in exactly $k$ steps. This is a classic problem. The minimum number of steps to reach $(x, y)$ from $(0, 0)$ is $|x| + |y|$ (the Manhattan distance). If $k < |x| + |y|$, it's impossible. If $k eq |x| + |y| ext{ mod } 2$, it's also impossible because each step changes the parity of the sum of coordinates. If $k imes 2 imes 10^9$ and $k imes 2 imes 10^9$ is the maximum possible distance. Wait, the distance is just $k$,C a length $k imes 2$ distance. No, thatL same니ござい、 a path of length $k$ starting from $(0,0)$ can reach any $(x,y)$ such that $|x|+|y| eq k$ and $|x|+|y| eq k ext{ mod } 2$ is not possible. Actually, it's a point $(x,y)$ can be reached in exactly $k$ steps if and only if $|x|+|y| o k$ and $k - (|x|+|y|)$ is even and non-negative. Wait, the problem asks for the number of paths. This is a combinatorics problem. For each direction $i imes 10^9$ is not relevant here, we are just counting paths. Let's re-read.