Day 06: Evaluation Forms

The exam is finally over, but there's no rest for the wicked: the peer-evaluation (defense) session starts immediately.

For each project evaluated in groups, correctors must complete an evaluation rubric on the Intra containing 26 questions labeled a through z (for instance: a for "Norminette compliant", b for "No memory leaks", c for "Makefile without relinking", etc.).

Each student ticks the criteria they personally verified. The results of an evaluation group are assembled in your input file: each person corresponds to a line listing the letters they validated, and defense groups are separated by a blank line.

Part 1

The Bocal begins with a preliminary check: for each group, they want to know how many distinct criteria were approved by at least one student in that group.

Example

Consider this survey sample:

abc

a
b
c

ab
ac

a
a
a
a

b

This report contains 5 defense groups:

• Group 1 (1 person): checked a, b, and c — for a total of 3 criteria approved.
• Group 2 (3 people): the 1st checked a, the 2nd b, the 3rd c — for a total of 3 criteria approved.
• Group 3 (2 people): the 1st approved a and b, the 2nd a and c — for a total of 3 criteria (a, b, c).
• Group 4 (4 people): everyone only checked a — for a total of 1 criterion approved.
• Group 5 (1 person): only approved b — for a total of 1 criterion approved.

The sum of these counts across all groups is 3 + 3 + 3 + 1 + 1 = 11.

Analyze all the groups in your input report. For each group, count the number of questions to which anyone answered yes. What is the sum of those counts?