ollien
/
advent-of-code-2020
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

Document day 5

master
Nick Krichevsky 2020-12-05 01:30:51 -05:00
parent 8ed21d9550
commit d8c1297bf3
1 changed files with 35 additions and 12 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

47
day5/day5.cpp
View File

@ -25,11 +25,19 @@ std::vector<std::string> read_input(const std::string &filename) {
return input;
}
int getPosFromSpec(std::string_view view, char bottomHalfChar, char topHalfChar, int initMax) {
/**
* Get the position of a row or a column from a string spec.
* @param spec The specification of the row or the column for the problem
* @param bottomHalfChar The character that specifies taking the bottom half of the row/column
* @param topHalfChar The character that specifies using the top half of the row/column
* @param initMax The initial maximum value for the unit being checked (row or column).
* @return int The row/column position from the spec.
*/
int getPosFromSpec(std::string_view spec, char bottomHalfChar, char topHalfChar, int initMax) {
int max = initMax;
int min = 0;
int stringCursor = 0;
for (char candidate : view) {
for (char candidate : spec) {
// std::cout << min << " " << max << std::endl;
// std::cout << candidate << std::endl;
if (candidate == topHalfChar) {
@ -44,9 +52,14 @@ int getPosFromSpec(std::string_view view, char bottomHalfChar, char topHalfChar,
return min;
}
int getColumnSplitPoint(std::string_view view) {
int rightPosition = view.find(RIGHT_CHAR);
int leftPosition = view.find(LEFT_CHAR);
/**
* Get the point at which the specification splits between row and column (i.e. from F/B and L/R)
* @param seatSpec The specification for the seat
* @return int The index at which rows stop being specified
*/
int getColumnSplitPoint(std::string_view seatSpec) {
int rightPosition = seatSpec.find(RIGHT_CHAR);
int leftPosition = seatSpec.find(LEFT_CHAR);
if (rightPosition == std::string_view::npos) {
return leftPosition;
} else if (leftPosition == std::string_view::npos) {
@ -56,19 +69,30 @@ int getColumnSplitPoint(std::string_view view) {
return std::min(rightPosition, leftPosition);
}
int parseSeatID(std::string_view view) {
int columnSplitPoint = getColumnSplitPoint(view);
std::string_view rowSpec = view.substr(0, columnSplitPoint);
std::string_view colSpec = view.substr(columnSplitPoint);
// std::cout << rowSpec << " " << colSpec << std::endl;
/**
* Get the seat ID from the seat specification
* @param seatSpec The specification for the seat specification
* @return int The seatID given by seatSpec
*/
int parseSeatID(std::string_view seatSpec) {
int columnSplitPoint = getColumnSplitPoint(seatSpec);
std::string_view rowSpec = seatSpec.substr(0, columnSplitPoint);
std::string_view colSpec = seatSpec.substr(columnSplitPoint);
int rowId = getPosFromSpec(rowSpec, BACK_CHAR, FRONT_CHAR, MAX_ROW);
int colId = getPosFromSpec(colSpec, RIGHT_CHAR, LEFT_CHAR, MAX_COL);
// std::cout << rowId << " " << colId << std::endl;
return rowId * (MAX_COL + 1) + colId;
}
/**
* Find the missing number in an iterator
* @tparam Iter The iterator to check in
* @param begin The start of the iterator
* @param end The end of the iterator
* @return std::iterator_traits<Iter>::value_type The missing number in the iterator
* @throws invalid_argument if there is no missing number in the iterator
*/
template <typename Iter>
typename std::iterator_traits<Iter>::value_type findMissingNumber(Iter begin, Iter end) {
auto lastNumber = *begin;
@ -83,7 +107,6 @@ typename std::iterator_traits<Iter>::value_type findMissingNumber(Iter begin, It
throw std::invalid_argument("No missing number in iterator");
}
int part1(const std::vector<std::string> &input) {
return std::accumulate(input.cbegin(), input.cend(), 0, [](int max, const std::string &row) {
int seatId = parseSeatID(row);