Connection Status:
Competition Arena > FoxAirline2

FoxAirline2

SRM 685 · 2016-03-02 · by cgy4ever

SRM 685 · 2016-03-02 · by cgy4ever · Graph Theory, Search
Class Name: FoxAirline2
Return Type: String
Method Name: isPossible
Arg Types: (int, vector<int>, vector<int>)
Problem Statement

Problem Statement

Fox Ciel has an airline company: Fox Airline. There are n airports in the region serviced by Fox Airline. The airports are numbered 0 through n-1. You are given the int n.

The company currently offers several bidirectional flights. You are given the information about these flights in the int[]s a and b: for each valid i there is a bidirectional flight that connects the airports a[i] and b[i]. Note that some pairs of airports may be connected by multiple direct flights.

Fox Airline is too big, so Ciel has to split it into two new companies. After the split, each of the current flights will belong to one of the two new companies.

We say that a company services the entire region if it is possible to travel between all cities in the region by just using flights of that company. Fox Ciel wants to know whether it is possible to split her company in such a way that each of the two new companies will service the entire region (i.e., all n cities). Return "Possible" if it can be done, and "Impossible" otherwise.

Constraints

  • n will be between 2 and 10, inclusive.
  • a will contain between 1 and 50 elements, inclusive.
  • a and b will contain the same number of elements.
  • Each element in a will be between 0 and n-1, inclusive.
  • Each element in b will be between 0 and n-1, inclusive.
  • For each i, a[i] != b[i].

Statement by TopCoder, Inc. — view the original on the archive.

Examples
0)
4
{0,0,0,1,1,2}
{1,2,3,2,3,3}
Returns: "Possible"

One possible solution is to assign the flights {(0,1), (0,2), (2,3)} to one company and the flights {(0,3), (1,2), (1,3)} to the other company.

1)
6
{0,0,0,0,1,1,1,2,2,3,0}
{1,2,3,4,2,3,4,3,4,4,5}
Returns: "Impossible"

Note that Ciel's current company has only one flight that visits airport 5. Regardless of how we divide the flights between the two new companies, one of those companies won't have any flights that visit airport 5.

2)
5
{0,0,0,1,1,2,2,3}
{1,2,4,2,4,3,4,4}
Returns: "Possible"
3)
2
{0,1,1}
{1,0,0}
Returns: "Possible"

Note that there may be multiple flights between some pairs of airports.

4)
10
{0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 5, 5, 5, 5, 6, 6, 6, 7, 7, 8}
{1, 2, 3, 4, 5, 6, 7, 8, 9, 2, 3, 4, 5, 6, 7, 8, 9, 3, 4, 5, 6, 7, 8, 9, 4, 5, 6, 7, 8, 9, 5, 6, 7, 8, 9, 6, 7, 8, 9, 7, 8, 9, 8, 9, 9}
Returns: "Possible"

Submissions are judged against all 200 archived test cases, of which 5 are shown here. Case numbers match the judge’s.

Coding Area

Language: C++17 · define a public class FoxAirline2 with a public method string isPossible(int n, vector<int> a, vector<int> b) · 200 test cases · 2 s / 256 MB per case

Submitting as anonymous