return std::equal(a.cbegin(), a.cend(), b.cbegin(),
[](const choice& choice_a, const choice& choice_b) {
return choice_a.first == choice_b.first &&
return std::equal(a.cbegin(), a.cend(), b.cbegin(),
[](const choice& choice_a, const choice& choice_b) {
return choice_a.first == choice_b.first &&