模拟森林火灾，元胞有三个状态，0是空位，1是燃烧的树，2是树木。如果4个邻居中有一个或者一个以上的是燃烧着的并且自身是树木，那么该元胞下一时刻的状态是燃烧。-Simulated forest fire, the cell has three states, 0 is the space, 1 is the burning tree, 2 is the tree. If one or more of the four neighbors are burning and are themselves trees, then the state of the cell is burning at the next moment.