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/*
This code is a bit ugly, day12b.cpp contains a nicer implementation
(the perimeter part is of course different).
*/
#include <iostream>
#include <algorithm>
#include <string>
#include <string_view>
#include <vector>
using namespace std;
enum class Direction { U, D, R, L };
Direction all_directions[] = {
Direction::U, Direction::D, Direction::R, Direction::L,
};
pair<int, int> step(pair<int, int> p, Direction d) {
auto [i, j] = p;
switch (d) {
case Direction::U:
return make_pair(i-1, j);
case Direction::D:
return make_pair(i+1, j);
case Direction::R:
return make_pair(i, j+1);
case Direction::L:
return make_pair(i, j-1);
}
return make_pair(-999,-999);
}
class Board {
public:
const char out_of_bound = '$';
int M, N;
Board(vector<string> &lines) {
N = lines.size();
M = 0;
for (string l : lines)
M = max(M, (int)l.size());
region = new int[M * N];
cells = new char[M * N];
for (int i = 0; i < N; i++) {
for (int j = 0; j < M; j++) {
region[N*i + j] = -1;
cells[N*i + j] = j < (int)lines[i].size() ?
lines[i][j] : out_of_bound;
}
}
}
~Board() {
delete []region;
delete []cells;
}
char operator[](pair<int, int> p) {
int c = coord(p);
return c == -1 ? out_of_bound : cells[c];
}
int& reg(pair<int, int> p) {
return region[coord(p)];
}
private:
char *cells;
int *region;
int coord(pair<int, int> p) {
auto [i, j] = p;
return i >= N || i < 0 || j >= M || j < 0 ? -1 : N*i + j;
}
};
void fill(pair<int, int> p, char a, int r, Board &board) {
if (board[p] != a || board.reg(p) == r)
return;
board.reg(p) = r;
fill(step(p, Direction::U), a, r, board);
fill(step(p, Direction::D), a, r, board);
fill(step(p, Direction::R), a, r, board);
fill(step(p, Direction::L), a, r, board);
}
int cell_perim(Board &board, pair<int, int> p) {
int perim = 0;
if (board[step(p, Direction::U)] != board[p]) perim++;
if (board[step(p, Direction::D)] != board[p]) perim++;
if (board[step(p, Direction::R)] != board[p]) perim++;
if (board[step(p, Direction::L)] != board[p]) perim++;
return perim;
}
int measure_region(Board &board, int r) {
int area = 0;
int perim = 0;
pair<int, int> p;
for (p.first = 0; p.first < board.N; p.first++) {
for (p.second = 0; p.second < board.M; p.second++) {
if (board.reg(p) == r) {
area++;
perim += cell_perim(board, p);
}
}
}
return area * perim;
}
int scan(Board &board, int maxr) {
int tot = 0;
for (int r = 0; r < maxr; r++)
tot += measure_region(board, r);
return tot;
}
int main() {
string line;
vector<string> lines;
while (getline(cin, line))
lines.push_back(line);
Board board(lines);
pair<int, int> p;
int r = 0;
for (p.first = 0; p.first < board.N; p.first++) {
for (p.second = 0; p.second < board.M; p.second++) {
if (board.reg(p) == -1) {
fill(p, board[p], r, board);
r++;
}
}
}
auto tot = scan(board, r);
cout << tot << endl;
return 0;
}
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