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#include <algorithm>
#include <cstdio>
#include <cstring>
#include <vector>

int countTime(std::vector<unsigned int> data)
{
    int time = 0;
    while (data.size() > 1) {
        std::vector<unsigned int> data2;
        if (data[0] > data[1]) {
            data2.push_back(data[0]);
        }
        for (unsigned int i = 1; i < data.size() - 1; ++i) {
            if (data[i - 1] < data[i] && data[i + 1] < data[i]) {
                data2.push_back(data[i]);
            }
        }
        if (data[data.size() - 1] > data[data.size() - 2]) {
            data2.push_back(data[data.size() - 1]);
        }
        time++;
        data = data2;
    }
    return time;
}

void generate(int* permutationsTime, const unsigned int n, unsigned int* data)
{
    std::vector<unsigned int> _data;
    do {
        for (unsigned int i = 0; i < n; ++i)
            _data.push_back(data[i]);
        const auto pt = countTime(_data);
        permutationsTime[pt]++;
        _data.clear();
    } while (std::next_permutation(data, data + n));
}

int main()
{
    unsigned int n, k, p;
    scanf("%u %u %u\n", &n, &k, &p);
    int* permutationsTime = new int[k + 1];
    for (unsigned int i = 0; i <= k; ++i) {
        permutationsTime[i] = 0;
    }
    unsigned int* data = new unsigned int[n];
    for (unsigned int i = 0; i < n; ++i)
        data[i] = i + 1;
    generate(permutationsTime, n, data);
    printf("%d\n", permutationsTime[k]);
    delete[] permutationsTime;
}