Electroneum
combinator.cpp
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30 
31 #include "combinator.h"
32 
33 namespace tools {
34 
36 {
37  if (k > n) {
38  throw std::runtime_error("k must not be greater than n");
39  }
40 
41  uint64_t c = 1;
42  for (uint64_t i = 1; i <= k; ++i) {
43  c *= n--;
44  c /= i;
45  }
46 
47  return c;
48 }
49 
50 }
uint64_t combinations_count(uint32_t k, uint32_t n)
Definition: combinator.cpp:35
unsigned int uint32_t
Definition: stdint.h:126
Various Tools.
Definition: tools.cpp:31
unsigned __int64 uint64_t
Definition: stdint.h:136