Commit b1176a9

@@ -1,67 +1,64 @@
 #include <stdio.h>
 #include <stdlib.h>
-#include "gol.h"
 #include <time.h>
+#include <math.h>
+#include <string.h>
+#include "gol.h"
+
+int alive(char value) {
+  return value == 'x' ? 1 : 0;
+};
 
-Cell find_cell(World world, int x, int y) {
-  for (int i = 0; i < world.number_of_cells; i++) {
-    Cell cell = world.cells[i];
-    if (cell.x == x && cell.y == y) {
-      return cell;
-    }
+int west_of(char* world, int index) {
+  if (index == 0 || index == 3 || index == 6) {
+    return alive(world[index + 2]);
   }
-  Cell null_cell;
-  null_cell.x = -1;
-  null_cell.y = -1;
-  null_cell.alive = ' ';
-  return null_cell;
+  return alive(world[index - 1]);
 }
 
-int living_neighbours_for(World world, Cell cell){
-  int west = find_cell(world, cell.y, cell.x - 1).alive == 'x' ? 1 : 0;
-  int east = find_cell(world, cell.y, cell.x + 1).alive == 'x' ? 1 : 0;
-  return west + east;
+int east_of(char* world, int index) {
+  if (index == 2 || index == 5 || index == 8) {
+    return alive(world[index - 2]);
+  }
+  return alive(world[index + 1]);
 }
 
-World evolve(World world) {
-  for (int i = 0; i < world.number_of_cells; i++) {
-    Cell cell = world.cells[i];
-    int neighbours = living_neighbours_for(world, cell);
-    cell.alive = (neighbours >= 2) ? 'x' : ' ';
+int north_of(char* world, int index) {
+  if (index == 0 || index == 1 || index == 2) {
+    return alive(world[index + 6]);
   }
-  return world;
+  return alive(world[index - 3]);
 }
 
-void print(World world) {
-  for (int i = 0; i < world.number_of_cells; i++) {
-    Cell cell = world.cells[i];
-    if (i % 3 == 0) { printf("\n---\n"); }
-    printf("%c", cell.alive);
+int south_of(char* world, int index) {
+  if (index == 6 || index == 7 || index == 8) {
+    return alive(world[index - 6]);
   }
-  printf("\n---\n");
+  return alive(world[index + 3]);
 }
 
-char random_life() {
-  /*srand(time(NULL));*/
-  /*return rand() % 7 == 0 ? 'x' : ' ';*/
-  return 'x';
+int living_neighbours_for(char* world, int index){
+  return west_of(world, index) + east_of(world, index) + north_of(world, index) + south_of(world, index);
 }
 
-World create_world(int height, int width){
-  World world;
-  Cell* cells = (Cell*)malloc(sizeof(Cell) * (height * width));
-  int cell_number = 0;
-  for (int y = 0; y < height; y++) {
-    for (int x = 0; x < width; x++) {
-      Cell cell;
-      cell.x = x;
-      cell.y = y;
-      cell.alive = random_life();
-      cells[cell_number] = cell;
-      ++cell_number;
-    }
+char* evolve(char* world) {
+  int number_of_cells = 9;
+  char new_world[number_of_cells + 1];
+  memset(new_world, ' ', number_of_cells);
+  new_world[number_of_cells] = 0;
+  for (int i = 0; i < number_of_cells; i++) {
+    int neighbours = living_neighbours_for(world, i);
+    new_world[i] = (neighbours >= 2) ? 'x' : ' ';
   }
-  world.cells = cells;
-  world.number_of_cells = height*width;
-  return world;
+  return new_world;
+}
+
+void print(char* world) {
+  int number_of_cells = 9;
+  for (int i = 0; i < number_of_cells; i++) {
+    char cell = world[i];
+    if (i % 3 == 0) { printf("\n---\n"); }
+    printf("%c", cell);
+  }
+  printf("\n---\n");
 }

@@ -1,16 +1,3 @@
-
-typedef struct {
-  int x;
-  int y;
-  char alive;
-} Cell;
-
-typedef struct {
-  Cell* cells;
-  int number_of_cells;
-} World;
-
-int living_neighbours_for(World world, Cell cell);
-World evolve(World world);
-void print(World world);
-World create_world(int height, int width);
+int living_neighbours_for(char* world, int index);
+char* evolve(char* world);
+void print(char* world);

@@ -11,40 +11,47 @@ static char* test_foo() {
 }
 
 static char* any_live_cell_with_fewer_than_two_live_neighbours_dies_as_if_caused_by_under_population() {
-  printf("%s\n", __func__);
+  printf("TEST: %s\n", __func__);
   char world[3][3] = {
     { 'x', ' ', ' ' },
     { ' ', ' ', ' ' },
     { ' ', ' ', ' ' },
   };
-  evolve(world);
-  assert_equal(world[0][1] == ' ', "should die because has 1 living neighbours");
-  assert_equal(world[2][2] == ' ', "should die because has 0 living neighbours");
+  char* new_world = evolve(*world);
+  printf("%s\n", new_world);
+  assert_equal(new_world[0] == ' ', "should die because has 1 living neighbours");
+  assert_equal(new_world[8] == ' ', "should die because has 0 living neighbours");
   return 0;
 }
 
 static char* any_live_cell_with_two_live_neighbours_lives_on_to_the_next_generation() {
-  printf("%s\n", __func__);
+  printf("TEST: %s\n", __func__);
   char world[3][3] = {
     { 'x', ' ', 'x' },
     { ' ', ' ', ' ' },
     { ' ', ' ', ' ' },
   };
-  char* new_world = evolve(world);
-  assert_equal(&new_world[0][1] == 'x', "should live because has 2 live neighbors");
+  char* new_world = evolve(*world);
+  assert_equal(new_world[1] == 'x', "should live because has 2 live neighbors");
   return 0;
 }
 
 static char* it_returns_the_correct_number_of_living_neighbors() {
-  printf("%s\n", __func__);
+  printf("TEST: %s\n", __func__);
   char world[3][3] = {
     { 'x', ' ', 'x' },
     { ' ', ' ', ' ' },
     { ' ', ' ', ' ' },
   };
-  assert_equal(living_neighbours_for(world, 0, 0) == 0, "should return 0");
-  assert_equal(living_neighbours_for(world, 1, 0) == 2, "should return 2");
-  assert_equal(living_neighbours_for(world, 0, 2) == 0, "should return 0");
+  assert_equal(living_neighbours_for(*world, 0) == 1, "0, 0 should return 1");
+  assert_equal(living_neighbours_for(*world, 1) == 2, "1, 0 should return 2");
+  assert_equal(living_neighbours_for(*world, 2) == 1, "2, 0 should return 1");
+  assert_equal(living_neighbours_for(*world, 3) == 1, "0, 1 should return 1");
+  assert_equal(living_neighbours_for(*world, 4) == 0, "1, 1 should return 0");
+  assert_equal(living_neighbours_for(*world, 5) == 1, "2, 1 should return 1");
+  assert_equal(living_neighbours_for(*world, 6) == 1, "0, 2 should return 1");
+  assert_equal(living_neighbours_for(*world, 7) == 0, "1, 2 should return 0");
+  assert_equal(living_neighbours_for(*world, 8) == 1, "2, 2 should return 1");
   return 0;
 }
 
@@ -64,7 +71,7 @@ static char* all_tests() {
 int main(int argc, char **argv) {
   char *result = all_tests();
   if (result != 0) {
-    printf("%s\n", result);
+    printf("FAILED: %s\n", result);
   }
   else {
     printf("ALL TESTS PASSED\n");

@@ -1,12 +1,19 @@
 #include <stdio.h>
 #include <stdlib.h>
+#include <unistd.h>
 #include "gol.h"
 
 int main(int argc, char **argv) {
-  World world = create_world(3, 3);
+  char world[3][3] = {
+    { ' ', ' ', ' ' },
+    { 'x', 'x', 'x' },
+    { ' ', ' ', ' ' },
+  };
   system("clear");
-  /*for (int i = 0; i < 5; i++) {*/
-    /*evolve(world);*/
-    print(world);
-  /*}*/
+  for (int i = 0; i < 5; i++) {
+    evolve(*world);
+    print(*world);
+    sleep(1);
+    system("clear");
+  }
 }