CHAIN - Strange Food Chain
There are 3 kinds of animals A,B and C. A can eat B,B can eat C,C can eat A. It's interesting,isn't it?
Now we have n animals,numbered from 1 to n. Each of them is one of the 3 kinds of animals:A,B,C.
Today Mary tells us k pieces of information about these n animals. Each piece has one of the two forms below:
- 1 x y: It tells us the kind of x and y are the same.
- 2 x y: It tells us x can eat y.
Some of these k pieces are true,some are false. The piece is false if it satisfies one of the 3 conditions below, otherwise it's true.
- X or Y in this piece is larger than n.
- This piece tells us X can eat X.
- This piece conflicts to some true piece before.
The first line contains a single integer t.t blocks follow.
To every block,the first line contains two integers n(1<=n<=50000) and k (1<=k<=100000). k lines follow,each contains 3 positive integers D(1<=D<=2),X,Y,separated by single spaces.
t lines,each contains a single integer - the number of false pieces in the corresponding block.
Sample input: 1 100 7 1 101 1 2 1 2 2 2 3 2 3 3 1 1 3 2 3 1 1 5 5 Sample output: 3 Hint:Warning: large Input/Output data, be careful with certain languages
The false pieces are the 1st,the 4th and the 5th ones.
this is cool :)Last edit: 2019-01-14 19:11:18
nice problem ):))
Best question on union-find!
why the sentence 5 is false??
Difference between scanf and my fast reading is 0.6s on this problem, so a lot of time is wasted on input reading. Still, with the proper algorithm in C++ you should have no problem with AC. In my case it was 0.7s, where the actual algo took under 0.1s.
IMHO time limit is too strict.