100 lines
2.9 KiB
C++
100 lines
2.9 KiB
C++
#include <iostream>
|
|
#include <regex>
|
|
#include <string>
|
|
|
|
auto swap_pos(std::string s, std::size_t a, std::size_t b) -> std::string
|
|
{
|
|
std::swap(s.at(a), s.at(b));
|
|
return s;
|
|
}
|
|
|
|
auto swap_letters(std::string const& s, char a, char b) -> std::string
|
|
{
|
|
std::string result;
|
|
std::transform(s.begin(), s.end(), std::back_inserter(result), [a, b](char c) {
|
|
if (c == a) {
|
|
return b;
|
|
}
|
|
if (c == b) {
|
|
return a;
|
|
}
|
|
return c;
|
|
});
|
|
return result;
|
|
}
|
|
|
|
auto rotate_left(std::string const& s, std::size_t amt) -> std::string
|
|
{
|
|
amt %= s.size();
|
|
return (s + s).substr(amt, s.size());
|
|
}
|
|
|
|
auto rotate_right(std::string const& s, std::size_t amt) -> std::string
|
|
{
|
|
amt %= s.size();
|
|
return (s + s).substr(s.size() - amt, s.size());
|
|
}
|
|
|
|
auto rotate_on_index(std::string const& s, char c) -> std::string
|
|
{
|
|
auto idx{s.find(c)};
|
|
std::size_t amt{1 + idx + (idx >= 4 ? 1 : 0)};
|
|
return rotate_right(s, amt);
|
|
}
|
|
|
|
auto reverse_str(std::string s, std::size_t a, std::size_t b) -> std::string
|
|
{
|
|
std::reverse(s.begin() + a, s.begin() + b + 1);
|
|
return s;
|
|
}
|
|
auto move(std::string s, std::size_t a, std::size_t b) -> std::string
|
|
{
|
|
auto c{s.at(a)};
|
|
s.erase(a, 1);
|
|
s.insert(s.begin() + b, c);
|
|
return s;
|
|
}
|
|
|
|
auto main() -> int
|
|
{
|
|
static std::regex swap_pos_re{"swap position (\\d+) with position (\\d+)"};
|
|
static std::regex swap_letter_re{"swap letter (.) with letter (.)"};
|
|
static std::regex rotate_left_re{"rotate left (\\d+) steps?"};
|
|
static std::regex rotate_right_re{"rotate right (\\d+) steps?"};
|
|
static std::regex rotate_based_re{"rotate based on position of letter (.)"};
|
|
static std::regex reverse_re{"reverse positions (\\d+) through (\\d+)"};
|
|
static std::regex move_re{"move position (\\d+) to position (\\d+)"};
|
|
|
|
std::string password{"abcdefgh"};
|
|
std::string line;
|
|
std::smatch m;
|
|
while (std::getline(std::cin, line)) {
|
|
if (std::regex_search(line, m, swap_pos_re)) {
|
|
password = swap_pos(password, std::stoul(m.str(1)), std::stoul(m.str(2)));
|
|
}
|
|
else if (std::regex_search(line, m, swap_letter_re)) {
|
|
password = swap_letters(password, m.str(1)[0], m.str(2)[0]);
|
|
}
|
|
else if (std::regex_search(line, m, rotate_left_re)) {
|
|
password = rotate_left(password, std::stoul(m.str(1)));
|
|
}
|
|
else if (std::regex_search(line, m, rotate_right_re)) {
|
|
password = rotate_right(password, std::stoul(m.str(1)));
|
|
}
|
|
else if (std::regex_search(line, m, rotate_based_re)) {
|
|
password = rotate_on_index(password, m.str(1)[0]);
|
|
}
|
|
else if (std::regex_search(line, m, reverse_re)) {
|
|
password = reverse_str(password, std::stoul(m.str(1)), std::stoul(m.str(2)));
|
|
}
|
|
else if (std::regex_search(line, m, move_re)) {
|
|
password = move(password, std::stoul(m.str(1)), std::stoul(m.str(2)));
|
|
}
|
|
else {
|
|
std::cerr << "Unable to interpret " << line << "\n";
|
|
return 1;
|
|
}
|
|
std::cout << line << " -> " << password << '\n';
|
|
}
|
|
std::cout << password << '\n';
|
|
} |