Combinations and permutations: Difference between revisions

=={{header|C++}}==

{{libheader|Boost}}

Compiled with <code>g++-10 -O2 -g -Wall -fmessage-length=0 -std=c++03</code>, linked with <code>-lgmp</code>

<lang cpp>#include <boost/multiprecision/gmp.hpp>

#include <iostream>

using namespace boost::multiprecision;

mpz_int p(uint n, uint p) {

mpz_int r = 1;

mpz_int k = n - p;

while (n > k)

r *= n--;

return r;

}

mpz_int c(uint n, uint k) {

mpz_int r = p(n, k);

while (k)

r /= k--;

return r;

}

int main() {

for (uint i = 1u; i < 12u; i++)

std::cout << "P(12," << i << ") = " << p(12u, i) << std::endl;

for (uint i = 10u; i < 60u; i += 10u)

std::cout << "C(60," << i << ") = " << c(60u, i) << std::endl;

return 0;

}</lang>

{{out}}

<pre>P(12,1) = 12

P(12,2) = 132

P(12,3) = 1320

P(12,4) = 11880

P(12,5) = 95040

P(12,6) = 665280

P(12,7) = 3991680

P(12,8) = 19958400

P(12,9) = 79833600

P(12,10) = 239500800

P(12,11) = 479001600

C(60,10) = 75394027566

C(60,20) = 4191844505805495

C(60,30) = 118264581564861424

C(60,40) = 4191844505805495

C(60,50) = 75394027566</pre>