Use grid as outparameter aswell

src/life.cpp

@@ -137,7 +137,7 @@ int gridAliveNeighbors(Grid<Cell> &grid, int row, int col) {
  *    - Locations with 3 neighbours will create life.
  *    - A cell with 4 or more neighbours dies.
  */
-Grid<Cell> gridTick(Grid<Cell> &grid) {
+void gridTick(Grid<Cell> &grid) {
     Grid<Cell> nextGrid = grid;
 
     for (int row = 0; row < grid.numRows(); row++) {
@@ -155,7 +155,7 @@ Grid<Cell> gridTick(Grid<Cell> &grid) {
         }
     }
 
-    return nextGrid;
+    grid = nextGrid;
 }
 
 int main() {
@@ -234,12 +234,12 @@ int main() {
         // We don't have to handle QUIT, since we do in the while check
         switch (action) {
         case MenuAction::TICK:
-            grid = gridTick(grid);
+            gridTick(grid);
             gridPrint(grid);
             break;
         case MenuAction::ANIMATE:
             for (int i = 0; i < ANIMATION_N_GENERATIONS; i++) {
-                grid = gridTick(grid);
+                gridTick(grid);
                 clearConsole();
                 gridPrint(grid);
                 pause(ANIMATION_SLEEP_MS);