#include <stdio.h>
long long binomial_coefficient(int n, int k) {
if (k > n - k) {
k = n - k;
}
long long result = 1;
for (int i = 1; i <= k; i++) {
result = result * (n - i + 1) / i;
}
return result;
}
int main() {
int n, k;
printf("%lld\n", binomial_coefficient
(n
, k
)); return 0;
}
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