循环标签之蛇和梯子游戏

//--------蛇和梯子游戏
//摇色子，向前走，蛇是后退，梯子是上升
let finalSquare = 25 //最终位置
//TODO:这啥意思？
var board = [Int](count: finalSquare + 1, repeatedValue: 0)
board[03] = +08; board[06] = +11; board[09] = +09; board[10] = +02
board[14] = -10; board[19] = -11; board[22] = -02; board[24] = -08
var square = 0      //现在位置
var diceRoll = 0    //骰子数字

//square不等于finalSquare永远不停止
//gameLoop标签表明是主循环

//掷筛子
gameLoop: while square != finalSquare
{
//骰子从1到6
if ++diceRoll == 7
{
//重置筛子数字
diceRoll = 1
}
//移动
switch square + diceRoll
{
case finalSquare:
// 到达最后一个方块，游戏结束
break gameLoop
case let newSquare where newSquare > finalSquare:
print(newSquare)
print("本次移动超出最后一个方块，重新开始")
// 超出最后一个方块，再掷一次骰子
continue gameLoop
default:
// 本次移动有效
square += diceRoll
square += board[square]
}
}
print("完成关卡!")