initial commit

.gitignore

@@ -0,0 +1 @@
+cgol

Makefile

@@ -0,0 +1,10 @@
+WARN = -Wall -Wextra -Wconversion -Wvla
+
+default:
+	$(CC) $(WARN) main.c -o cgol
+
+debug:
+	$(CC) $(WARN) -g3 main.c -o cgol
+
+run: default
+	./cgol

main.c

@@ -0,0 +1,109 @@
+#include <stdio.h>
+
+#define WIDTH 213
+#define HEIGHT 56
+
+#define F_ARGS _Bool board[HEIGHT][WIDTH], int neighbours[HEIGHT][WIDTH], int y, int x
+
+int get_neighbours(_Bool board[HEIGHT][WIDTH], int y, int x)
+{
+    int neighbours = 0;
+
+    if(y > 0)
+    {
+        if(board[y - 1][x]) ++neighbours; // n
+
+    	if((x + 1) < WIDTH && board[y - 1][x + 1]) ++neighbours; // ne
+        if( x > 0          && board[y - 1][x - 1]) ++neighbours; // nw
+    }
+
+    if((x + 1) < WIDTH && board[y][x + 1]) ++neighbours; // e
+    if( x > 0         && board[y][x - 1]) ++neighbours; // w
+
+    if((y + 1) < HEIGHT)
+    {
+        if(board[y + 1][x]) ++neighbours; // s
+
+        if((x + 1) < WIDTH && board[y + 1][x + 1]) ++neighbours; // se
+        if( x > 0          && board[y + 1][x - 1]) ++neighbours; // sw
+    }
+
+    return neighbours;
+}
+
+void iter(void (*f)(F_ARGS), _Bool board[HEIGHT][WIDTH], int neighbours[HEIGHT][WIDTH])
+{
+    for(int y = 0; y < HEIGHT; ++y)
+    {
+        for(int x = 0; x < WIDTH; ++x)
+        {
+            (*f)(board, neighbours, y, x);
+        }
+    }
+}
+
+void print_board_pos(F_ARGS)
+{
+    board[y][x] ? putc('*', stdout) : putc('.', stdout);
+    if(x + 1 == WIDTH)
+        putc('\n', stdout);
+}
+
+void calculate_neighbours(F_ARGS)
+{
+    neighbours[y][x] = get_neighbours(board, y, x);
+}
+
+void apply_rules(F_ARGS)
+{
+    if(neighbours[y][x] < 2 || neighbours[y][x] > 3)
+    {
+        board[y][x] = 0;
+    }
+    else if(neighbours[y][x] == 3)
+    {
+        board[y][x] = 1;
+    }
+}
+
+int handle_input(int input)
+{
+    switch(input)
+    {
+        case 'q':
+            return 0;
+        default:
+            return 1;
+    }
+}
+
+int main(void)
+{
+    _Bool board[HEIGHT][WIDTH] = { 0 };
+    int neighbours[HEIGHT][WIDTH] = { 0 };
+
+    board[0][1] = 1;
+    board[1][2] = 1;
+    board[2][0] = 1;
+    board[2][1] = 1;
+    board[2][2] = 1;
+
+    iter(&print_board_pos, board, neighbours);
+    
+    int input = getchar();
+    _Bool run = handle_input(input);
+
+    while(run)
+    {
+        iter(&calculate_neighbours, board, neighbours);
+
+        iter(&apply_rules, board, neighbours);
+
+        iter(&print_board_pos, board, neighbours);
+
+        input = getchar();
+        run = handle_input(input);
+    }
+
+    return 0;
+}