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Sunday, 2 October 2022

[Solution] Meta-set Codeforces Solution



D. Meta-set
time limit per test
4 seconds
memory limit per test
256 megabytes
input
standard input
output
standard output

You like the card board game "Set". Each card contains k features, each of which is equal to a value from the set {0,1,2}. The deck contains all possible variants of cards, that is, there are 3k different cards in total.

A feature for three cards is called good if it is the same for these cards or pairwise distinct. Three cards are called a set if all k features are good for them.

For example, the cards (0,0,0)(0,2,1), and (0,1,2) form a set, but the cards (0,2,2)(2,1,2), and (1,2,0) do not, as, for example, the last feature is not good.

A group of five cards is called a meta-set, if there is strictly more than one set among them. How many meta-sets there are among given n distinct cards?

Input

The first line of the input contains two integers n and k (1n1031k20) — the number of cards on a table and the number of card features. The description of the cards follows in the next n lines.

Each line describing a card contains k integers ci,1,ci,2,,ci,k (0ci,j2) — card features. It is guaranteed that all cards are distinct.

Output

Output one integer — the number of meta-sets.

Note

Let's draw the cards indicating the first four features. The first feature will indicate the number of objects on a card: 123. The second one is the color: red, green, purple. The third is the shape: oval, diamond, squiggle. The fourth is filling: open, striped, solid.

You can see the first three tests below. For the first two tests, the meta-sets are highlighted.

In the first test, the only meta-set is the five cards (0000, 0001, 0002, 0010, 0020). The sets in it are the triples (0000, 0001, 0002) and (0000, 0010, 0020). Also, a set is the triple (0100, 1000, 2200) which does not belong to any meta-set.

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