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#include <stdio.h>
#include <stdlib.h>
#include <string.h>
struct Grid {
int h, w;
char c[128][128];
};
static char at(const struct Grid *grid, int y, int x) {
if (x < 0 || y < 0 || x >= grid->w || y >= grid->h) return '.';
return grid->c[y][x];
}
static int adj(const struct Grid *grid, int y, int x) {
return (
(at(grid, y - 1, x - 1) == '#') +
(at(grid, y - 1, x + 0) == '#') +
(at(grid, y - 1, x + 1) == '#') +
(at(grid, y + 0, x - 1) == '#') +
(at(grid, y + 0, x + 1) == '#') +
(at(grid, y + 1, x - 1) == '#') +
(at(grid, y + 1, x + 0) == '#') +
(at(grid, y + 1, x + 1) == '#')
);
}
static struct Grid gen(const struct Grid *prev) {
struct Grid next = { .h = prev->h, .w = prev->w };
for (int y = 0; y < next.h; ++y) {
for (int x = 0; x < next.w; ++x) {
if (prev->c[y][x] == 'L' && !adj(prev, y, x)) {
next.c[y][x] = '#';
} else if (prev->c[y][x] == '#' && adj(prev, y, x) >= 4) {
next.c[y][x] = 'L';
} else {
next.c[y][x] = prev->c[y][x];
}
}
}
return next;
}
int main(void) {
struct Grid init = {0};
while (EOF != scanf("%s\n", init.c[init.h])) {
init.h++;
}
init.w = strlen(init.c[0]);
struct Grid prev = init;
for (;;) {
struct Grid next = gen(&prev);
if (!memcmp(&next, &prev, sizeof(next))) break;
prev = next;
}
int occ = 0;
for (int y = 0; y < prev.h; ++y) {
for (int x = 0; x < prev.w; ++x) {
occ += prev.c[y][x] == '#';
}
}
printf("%d\n", occ);
}
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