diff options
Diffstat (limited to 'day15.cc')
-rw-r--r-- | day15.cc | 29 |
1 files changed, 29 insertions, 0 deletions
diff --git a/day15.cc b/day15.cc new file mode 100644 index 0000000..55a3d6d --- /dev/null +++ b/day15.cc @@ -0,0 +1,29 @@ +#include <iostream> + +using namespace std; + +template <int const n=0> +struct lrng { + uint64_t m, s; + uint16_t operator*() const { return s; } + auto operator++() { do s = s * m % 2147483647; while (n && s % n != 0); } +}; + +int +main() { + int p1{0}, p2{0}; + + lrng<> a1{16807, 634}; + lrng<> b1{48271, 301}; + for (long i{0}; i < 40'000'000; ++i, ++a1, ++b1) + if (*a1 == *b1) + p1++; + + lrng<4> a2{16807, 634}; + lrng<8> b2{48271, 301}; + for (long i{0}; i < 5'000'000; ++i, ++a2, ++b2) + if (*a2 == *b2) + p2++; + + cout << p1 << endl << p2 << endl; // 573 294 +} |