U517303 「ALFR Round 3」A Naughty Student

[Chinese Statement](P11445). In the school where Little Shan studies, there is a group of very naughty students. For example, when rating the teaching quality of their teachers, they seldom follow the requirements.

The teaching quality competition is about to begin. Each student can rate one of the three major subject teachers (Chinese, math, and English) in their class. Each student should rate only one teacher. However, some students may rate multiple teachers or not rate any teacher at all. We call such students naughty students. Given the rating situation of the teachers in the three subjects, please determine the number of naughty students in Little Shan's class.

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In the sample, students with IDs $1, 2, 3, 4, 5$ have respectively rated of $2, 2, 3, 0, 1$ to the teachers. Thus, students with IDs $1, 2, 3,4$ are all naughty students, so the answer is $4$. | Subtask | Score | Constraints | | :-----: | :---: | :---------: | | $0$ | $10$ | $n=1$ | | $1$ | $20$ | All elements in the arrays $x, y, z$ are distinct | | $2$ | $10$ | $a=b=c=1$ | | $3$ | $10$ | $a=n, b=c=1$ | | $4$ | $20$ | Arrays $x, y, z$ are provided in ascending order | | $5$ | $30$ | - | For all the tests, $1 \leq n \leq 100$, $0 \leq a, b, c \leq n$, and $1 \leq x_i, y_i, z_i \leq n$. The arrays $x, y, z$ have no duplicate elements within themselves.