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Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.

HTML

            
              <div id="root"></div>
            
          
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CSS

            
              body {
  margin: 0;
  padding: 0;
  background-color: #E6E7E8;
}
            
          
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JS

            
              const routeReducers = reducers => (state, action) =>
  reducers[action.type] ? reducers[action.type](state, action) : state;

const CellType = {
  EMPTY: "EMPTY",
  OLD: "OLD",
  NEW: "NEW"
};

const grid = (rows, cols, value) => {
  let cells = [];
  for (let i = 0, j; i < rows; i++) {
    cells[i] = [];
    for (j = 0; j < cols; j++) {
      cells[i][j] = value(i, j);
    }
  }
  return cells;
};

const setCellType = (cellType, cells, position) =>
  cells.map(
    (row, rowIndex) =>
      rowIndex === position.row
        ? row.map(
            (col, colIndex) =>
              colIndex === position.col ? { type: cellType } : col
          )
        : row
  );

const get = (row, col, cells) => {
  const rowLength = cells.length,
    colLength = cells[0].length;
  return cells[(row + rowLength) % rowLength][(col + colLength) % colLength];
};

const aliveNeighbours = (row, col, cells) =>
  [
    get(row - 1, col - 1, cells),
    get(row - 1, col, cells),
    get(row - 1, col + 1, cells),
    get(row, col - 1, cells),
    get(row, col + 1, cells),
    get(row + 1, col - 1, cells),
    get(row + 1, col, cells),
    get(row + 1, col + 1, cells)
  ].filter(cell => cell.type !== CellType.EMPTY).length;

const next = (row, col, cells) => {
  const cell = cells[row][col],
    neighbours = aliveNeighbours(row, col, cells);
  switch (cell.type) {
    case CellType.EMPTY:
      return neighbours === 3 ? { type: CellType.NEW } : cell;
    case CellType.NEW:
    case CellType.OLD:
      return neighbours === 2 || neighbours === 3
        ? { type: CellType.OLD }
        : { type: CellType.EMPTY };
    default:
      return cell;
  }
};

const store = Redux.createStore(
  routeReducers({
    initialize: (state, action) => {
      const cellTypes = [CellType.EMPTY, CellType.NEW, CellType.OLD];
      return {
        cells: grid(50, 50, () => ({
          type: cellTypes[Math.floor(Math.random() * 3)]
        })),
        generation: 0
      };
    },
    tick: (state, action) => ({
      ...state,
      cells: state.cells.map((row, rowIndex) =>
        row.map((col, colIndex) => next(rowIndex, colIndex, state.cells))
      ),
      generation: state.generation + 1
    }),
    toggle: (state, action) => {
      let cell = state.cells[action.position.row][action.position.col];
      switch (cell.type) {
        case CellType.EMPTY:
          return {
            ...state,
            cells: setCellType(CellType.NEW, state.cells, action.position)
          };
        case CellType.NEW:
        case CellType.OLD:
          return {
            ...state,
            cells: setCellType(CellType.EMPTY, state.cells, action.position)
          };
        default:
          return state;
      }
    },
    clear: (state, action) => ({
      cells: grid(50, 50, () => ({ type: CellType.EMPTY })),
      generation: 0
    }),
    setTimer: (state, action) => ({
      ...state,
      timer: action.timer
    })
  })
);

const run = () => {
  if (!store.getState().timer)
    store.dispatch({
      type: "setTimer",
      timer: setInterval(() => store.dispatch({ type: "tick" }), 100)
    });
};

const pause = () => {
  const timer = store.getState().timer;
  if (timer) store.dispatch({ type: "setTimer", timer: clearInterval(timer) });
};

const toggle = position => {
  store.dispatch({ type: "toggle", position });
};

const clear = () => {
  pause();
  store.dispatch({ type: "clear" });
};

const Header = () => {
  const headerStyle = {
    textAlign: "center",
    fontFamily: "Luckiest Guy",
    fontSize: "40px",
    color: "#01848F",
    marginTop: '10px'
  };
  return <div style={headerStyle}>Game Of Life</div>;
};

const Cell = ({ type, position }) => {
  const cellStyle = {
    width: "12px",
    height: "12px",
    border: "1px solid #9E9E9E",
    display: "inline-block",
    backgroundColor: type === CellType.NEW
      ? "#B2EBF2"
      : type === CellType.OLD ? "#006064" : "white"
  };
  return <div style={cellStyle} onClick={() => toggle(position)} />;
};

const CellRow = ({ row, rowIndex }) => {
  const rowStyle = {
    height: "12px",
    textAlign: "center"
  };
  return (
    <div style={rowStyle}>
      {row.map((cell, colIndex) =>
        <Cell
          type={cell.type}
          key={colIndex}
          position={{ row: rowIndex, col: colIndex }}
        />
      )}
    </div>
  );
};

const CellBoard = ({ cells }) => {
  return (
    <div>
      {cells.map((row, rowIndex) =>
        <CellRow row={row} key={rowIndex} rowIndex={rowIndex} />
      )}
    </div>
  );
};

const ActionButton = ({ buttonLabel, clickHandler }) => {
  const buttonStyle = {
    margin: "5px",
    padding: "5px",
    minWidth: "100px",
    backgroundColor: '#79C7C1',
    color: 'white',
    border: '1px solid transparent',
    fontSize: '18px',
    borderRadius: '5px',
    fontFamily: 'Open Sans',
    cursor: 'pointer'
  };
  return (
    <button style={buttonStyle} onClick={clickHandler}>{buttonLabel}</button>
  );
};

const Generation = ({ generation }) => {
  const generationStyle = {
    fontFamily: 'Open Sans',
    fontSize: '20px',
    color: '#01848F'
  };
  return <div style={generationStyle}>Generation: {generation}</div>;
};

const UserActions = ({
  runHandler,
  pauseHandler,
  clearHandler,
  generation
}) => {
  const actionStyle = {
    textAlign: "center",
    margin: "10px"
  };
  return (
    <div style={actionStyle}>
      <ActionButton buttonLabel="Run" clickHandler={run} />
      <ActionButton buttonLabel="Pause" clickHandler={pause} />
      <ActionButton buttonLabel="Clear" clickHandler={clear} />
      <Generation generation={generation} />
    </div>
  );
};

const App = ({ state }) => {
  return (
    <div>
      <Header />
      <UserActions generation={state.generation} />
      <CellBoard cells={state.cells} />
    </div>
  );
};

const render = () =>
  ReactDOM.render(
    <App state={store.getState()} />,
    document.getElementById("root")
  );

const isClear = (cells) => {
  for(let i = 0, j; i < cells.length; i++) {
    for(j = 0; j < cells[0].length; j++) {
      if(cells[i][j].type !== CellType.EMPTY) return false;
    }
  }
  return true;
}

store.subscribe(() => {
  const state = store.getState();
  if(state.timer && isClear(state.cells)) clear();
});
store.subscribe(render);

store.dispatch({type:'initialize'});
run();

            
          
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