Lonely Island#9044
There are several islands connected by one-way bridges: if a bridge connects islands and , you can use it only to go from to , but not back. When you are on island , you choose uniformly at random one of the islands directly reachable from by a one-way bridge and move to that island. You get stuck on an island if you cannot move any further. It is guaranteed that once you leave an island, you can never return to it.
Find the island on which you are most likely to get stuck. Two islands are considered equally likely if the absolute difference between the probabilities of getting stuck on them does not exceed 10^{-9}.
The first line contains three integers: the number of islands n~(1 \le n \le 2 \cdot 10^5), the number of one-way bridges m~(1 \le m \le 5 \cdot 10^5) and the index r~(1 \le r \le n) of the island where you start. Each of the next lines contains two integers u_i and v_i~(1 \le u_i, v_i \le n), describing a one-way bridge from island u_i to island v_i.
Print the index of the island on which you are most likely to get stuck. If there are several such islands, print all their indices in increasing order on a single line.
Example 1