15 lines
309 B
C++
15 lines
309 B
C++
#include <bits/stdc++.h>
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using namespace std;
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int main() {
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// 15 3 4
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int n, a, b;
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cin >> n >> a >> b;
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n -= a * (b - 1);
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n--, a--;
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int x = 1, y = 1;
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for (int i = n; i > n - a; i--) x *= i;
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for (int i = a; i; i--) y *= i;
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printf("%d\n", x / y);
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return 0;
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} |