X-Git-Url: https://git.wirehaze.ovh/lifeboot.git/blobdiff_plain/693fc5383745f0999d9fa5348c2a3d6ffc2f8e5e..9b01c6d143b14bc040f4ca7746cf926a4913cf92:/prototype.c?ds=sidebyside

diff --git a/prototype.c b/prototype.c
index 405654e..c297953 100644
--- a/prototype.c
+++ b/prototype.c
@@ -1,6 +1,8 @@
 #include <stdio.h>
 #include <stdlib.h>
+#include <string.h>
 #include <time.h>
+#include <unistd.h>
 
 #define COLS 80
 #define ROWS 25
@@ -8,18 +10,14 @@
 #define DEAD ' '
 #define ALIVE '#'
 
-#define INIT_RATIO 10
+#define INIT_RATIO 4
 
 #define STR(x) _STR(x)
 #define _STR(x) #x
 
-static void clearscr() {
-  printf("\e[1;1H\e[2J");
-}
+static void clearscr() { printf("\e[1;1H\e[2J"); }
 
-static void print_row(char row[COLS]) {
-  printf("%." STR(COLS) "s\n", row);
-}
+static void print_row(char row[COLS]) { printf("%." STR(COLS) "s\n", row); }
 
 static void print_grid(char grid[COLS * ROWS]) {
   for (int i = 0; i < ROWS; i++)
@@ -27,7 +25,7 @@ static void print_grid(char grid[COLS * ROWS]) {
 }
 
 static void init_grid(char grid[COLS * ROWS]) {
-  for (int i = 0; i < ROWS * COLS; i++) {
+  for (int i = 0; i < COLS * ROWS; i++) {
     if (rand() % INIT_RATIO)
       grid[i] = DEAD;
     else
@@ -35,14 +33,65 @@ static void init_grid(char grid[COLS * ROWS]) {
   }
 }
 
-int main () {
+static char get_state(char grid[COLS * ROWS], int row, int col) {
+  if (row < 0 || row >= ROWS || col < 0 || col >= COLS)
+    return DEAD;
+
+  return grid[row * COLS + col];
+}
+
+static int alive_neighbours(char grid[COLS * ROWS], int idx) {
+  int row = idx / COLS;
+  int col = idx % COLS;
+  int neighbours = 0;
+
+  for (int i = -1; i <= 1; i++)
+    for (int j = -1; j <= 1; j++)
+      if (get_state(grid, row + i, col + j) == ALIVE)
+        neighbours++;
+
+  if (get_state(grid, row, col) == ALIVE)
+    neighbours--;
+
+  return neighbours;
+}
+
+static char next_state(char grid[COLS * ROWS], int idx) {
+  int n = alive_neighbours(grid, idx);
+
+  if (get_state(grid, idx / COLS, idx % COLS) == ALIVE) {
+    if (n < 2 || n > 3)
+      return DEAD;
+
+    return ALIVE;
+  }
+
+  if (n == 3)
+    return ALIVE;
+
+  return DEAD;
+}
+
+static void update_grid(char grid[COLS * ROWS]) {
+  char new[COLS * ROWS];
+
+  for (int i = 0; i < COLS * ROWS; i++)
+    new[i] = next_state(grid, i);
+
+  memcpy(grid, new, COLS * ROWS);
+}
+
+int main() {
   char grid[COLS * ROWS];
 
   srand(time(0));
   init_grid(grid);
 
-  clearscr();
-  print_grid(grid);
+  do {
+    clearscr();
+    print_grid(grid);
+    update_grid(grid);
+  } while (getchar() != 'q');
 
   return 0;
 }