Count Good Numbers

A number is called good if its digits are strictly increasing from left to right. For example, 123 and 1579 are good numbers, whereas 112 and 321 are not.

For a given positive integer \(N\), count the number of good numbers of length \(N\). Notice that a good number is simply a selection of \(N\) distinct digits chosen from \(\{1, 2, \dots, 9\}\) arranged in increasing order. By combinatorial reasoning, the answer is given by the binomial coefficient \(\binom{9}{N}\).

The input is provided via standard input, and your program should output the result to standard output. If the provided \(N\) is not in the range \([1, 9]\), output the error message "N must be between 1 and 9 inclusive".

inputFormat

The input consists of a single integer \(N\) read from standard input.

outputFormat

If \(N\) is between 1 and 9 (inclusive), output a single line containing the number of good numbers of length \(N\), computed as \(\binom{9}{N}\). Otherwise, output the error message "N must be between 1 and 9 inclusive".

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