POLQUERY - Police Query

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To help capture criminals on the run, the police are introducing a new computer system. The area covered by the police contains N cities and E bidirectional roads connecting them. The cities are labelled 1 to N. The police often want to catch criminals trying to get from one city to another. Inspectors, looking at a map, try to determine where to set up barricades and roadblocks.

The new computer system should answer the following two types of queries:

1. Consider two cities A and B, and a road connecting cities G1 and G2. Can the criminals get from city A to city B if that one road is blocked and the criminals can't use it?

2. Consider three cities A, B and C. Can the criminals get from city A to city B if the entire city C is cut off and the criminals can't enter that city?

Write a program that implements the described system.


The first line contains two integers N and E (2 ≤ N ≤ 105, 1 ≤ E ≤ 5*105), the number of cities and roads. Each of the following E lines contains two distinct integers between 1 and N – the labels of two cities connected by a road. There will be at most one road between any pair of cities.

The following line contains the integer Q (1 ≤ Q ≤ 105), the number of queries the system is being tested on. Each of the following Q lines contains either four or five integers. The first of these integers is the type of the query – 1 or 2.

If the query is of type 1, then the same line contains four more integers A, B, G1 and G2 as described earlier. A and B will be different. G1 and G2 will represent an existing road.

If the query is of type 2, then the same line contains three more integers A, B and C. A, B and C will be distinct integers.

The test data will be such that it is initially possible to get from each city to every other city.


Output the answers to all Q queries, one per line. The answer to a query can be da (yes) or ne (no).


13 15
1 2
2 3
3 5
2 4
4 6
2 6
1 4
1 7
7 8
7 9
7 10
8 11
8 12
9 12
12 13
1 5 13 1 2
1 6 2 1 4
1 13 6 7 8
2 13 6 7
2 13 6 8


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Zhouxing Shi: 2013-04-09 01:49:13

@Abir YES!! And the problem is really nice!!

Last edit: 2013-04-09 04:58:59
Ja Issa Tai: 2012-11-12 08:48:31

sample input contains 5 queries, sample output contains only 4?

~!(*(@*!@^&: 2009-05-28 20:04:50

da = yes, ne = no

[Trichromatic] XilinX: 2009-05-28 20:04:50

The output (in your submitted program) must be "da" or "ne" (don't mind the sample).

Edit: Q is less than 300000 (not 100000).

Last edit: 2009-05-21 03:18:14
Abir: 2009-05-28 20:04:50

Resource should be COI 07.

Robert Gerbicz: 2009-05-28 20:04:50

"The answer to a query
can be "da" or "ne"."

So the sample output is wrong. (da=yes, ne=no)

Added by:~!(*(@*!@^&
Time limit:1s
Source limit:50000B
Memory limit:1536MB
Cluster: Cube (Intel G860)
Resource:COI 08