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#include <algorithm> |
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#include <iomanip> |
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#include <iostream> |
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using namespace std; |
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double power(double base, int exponential) { |
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if (exponential == 0) |
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return 1; |
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else if (exponential == 1) |
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return base; |
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double ans = power(base, exponential / 2); |
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if (exponential & 1) |
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return ans * ans * base; |
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return ans * ans; |
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} |
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int main() { |
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cin.tie(0); |
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ios_base::sync_with_stdio(0); |
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int n_testcase; |
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cin >> n_testcase; |
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while (n_testcase--) { |
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int n_people, index; |
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double probability; |
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cin >> n_people >> probability >> index; |
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double q = 1 - probability; |
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double common_ratio = power(q, n_people); |
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if (common_ratio == 1) |
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cout << "0.0000\n"; |
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else |
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cout << setprecision(4) << fixed << power(q, index - 1) * probability / (1 - common_ratio) << "\n"; |
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} |
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} |
