Teach Me
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Each employee knows up to 5 skills. Count ordered pairs (i, j) where employee i knows some skill that employee j does not.
- Level
Medium6 of 10
- Topics
- Bit manipulation, Combinatorics, Math, Hash map
- Solved
- No attempts yet
Problem
Here at Google we love teaching new skills to each other. There are N employees at Google, numbered from 1 to N. There are S different skills, numbered from 1 to S. Each employee knows at most 5 different skills.
The i-th employee can mentor the j-th employee if there is a skill that the i-th employee knows and the j-th employee does not know. How many ordered pairs (i, j) are there where the i-th employee can mentor the j-th employee?
Input
The first line of the input gives the number of test cases, T. T test cases follow. The first line of each test case gives the two integers N and S, which are the number of employees and the number of skills respectively.
The next N lines describe the skills that each employee knows. The i-th of these lines begins with an integer Ci, the number of skills the i-th employee knows. Then Ci integers follow on the same line. The j-th of these integers is Aij, meaning that the i-th employee knows the skill Aij.
Output
For each test case, output one line containing Case #x: y, where x is the test case number (starting from 1) and y is the number of ordered pairs (i, j) where the i-th employee can mentor the j-th employee.
Limits
- 1 ≤ T ≤ 100.
- 1 ≤ S ≤ 1000.
- 1 ≤ Ci ≤ 5 for all i.
- 1 ≤ Aij ≤ S for all i and j.
- Aij ≠ Aik for all j ≠ k.