COCI '20 Contest 4 #3 Hop

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Points: 25 (partial)
Time limit: 1.0s
Memory limit: 512M

Problem type

There are n water lilies, numbered 1 through n, in a line. On the ith lily there is a positive integer xi, and the sequence (xi)1in is strictly increasing.

Enter three frogs.

Every pair of water lilies (a,b), where a<b, must belong to frog 1, frog 2, or frog 3.

A frog can hop from water lily i to water lily j>i if the pair (i,j) belongs to it, and xi divides xj.

Distribute the pairs among the frogs such that no frog can make more than 3 consecutive hops.

Input Specification

The first line contains a positive integer n (1n1000), the number of water lilies.

The second line contains n positive integers xi (1xi1018), the numbers on the water lilies.

Output Specification

Output n1 lines. In the ith line, output i numbers, where the jth number is the label of the frog to which (j,i+1) belongs.

Constraints

Subtask Points Constraints
1 10 n30
2 100 No additional constraints.

If in your solution some frog can make k consecutive hops, where k>3, but no frog can make k+1 consecutive hops, your score for that test case is f(k)x points, where

f(x)=110{11kif 4k58k/2if 6k111if 12k190if k20

and x is the number of points for that subtask.

The score for some subtask equals the minimum score which your solution gets over all test cases in that subtask.

Sample Input 1

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8
3 4 6 9 12 18 36 72

Sample Output 1

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1
2 3
1 2 3
1 2 3 1
2 3 1 2 3
1 2 3 1 2 3
1 2 3 1 2 3 1

Explanation

1

The frogs are marked blue (1), green (2), and red (3).

The blue frog can hop from water lily x1=3 to water lily x4=9, then to water lily x7=36, and then to x8=72. These are the only three consecutive hops any frog can make.

The green frog can hop from water lily x2=4 to water lily x5=12, and then to x7=36, because 4 divides 12, and 12 divides 36. Those are two consecutive hops.

The red frog cannot hop from water lily x2=4 to water lily x3=6 because 6 is not divisible by 4.

No frog can make more than three consecutive hops.

Sample Input 2

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2
10 101

Sample Output 2

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1

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