面试——其他问题
其他
面试例题1：MARS ROVERS问题。[美国著名软件公司T面试题]
A squad of robotic rovers are to be landed by NASA on a plateau on Mars.
This plateau, which is curiously rectangular, must be navigated by the rovers so that their on-board cameras can get a complete view of the surrounding terrain to send back to Earth.
A rover's position and location is represented by a combination of x and y co-ordinates and a letter representing one of the four cardinal compass points. The plateau is divided up into a grid to simplify navigation. An example position might be 0, 0, N, which means the rover is in the bottom left corner and facing North.
In order to control a rover, NASA sends a simple string of letters. The possible letters are 'L', 'R' and 'M'. 'L' and 'R' makes the rover spin 90 degrees left or right respectively, without moving from its current spot.
'M' means move forward one grid point, and maintain the same heading. Assume that the square directly North from (x, y) is (x, y+1).
INPUT
The first line of input is the upper-right coordinates of the plateau, the lower-left coordinates are assumed to be 0,0.
The rest of the input is information pertaining to the rovers that have been deployed. Each rover has two lines of input. The first line gives the rover's position, and the second line is a series of instructions telling the rover how to explore the plateau.
The position is made up of two integers and a letter separated by spaces, corresponding to the x and y co-ordinates and the rover's orientation.
Each rover will be finished sequentially, which means that the second rover won't start to move until the first one has finished moving.
OUTPUT
The output for each rover should be its final co-ordinates and heading.
INPUT AND OUTPUT
Test Input:
5 5
1 2 N
LMLMLMLMM
3 3 E
MMRMMRMRRM
Test Output:
1 3 N
5 1 E
火星探测器问题。
一小队机器人探测器将由NASA送上火星高原，探测器将在这个奇特的矩形高原上行驶。用它们携带的照相机将周围的全景地势图发回地球。
每个探测器的方向和位置将由一个（x, y）系坐标图和一个表示地理方向的字母表示出来。为了方便导航，平原将被划分为网格状。位置坐标示例：0，0，N，表示探测器在坐标图的左下角，且面朝北方。为控制探测器，NASA会传送一串简单的字母。可能传送的字母为：“L”、“R”和“M”。“L”和“R”分别表示使探测器向左、向右旋转90o，但不离开它所在地点。“M”表示向前开进一个网格的距离，且保持方向不变。假设以广场（高原）的正北方向为Y轴的指向。
输入：首先输入的line是坐标图的右上方。假定左下方顶点的坐标为（0, 0）。剩下的要输入的是被分布好的探测器的信息。每个探测器需要输入两个lines。第一条line 提供探测器的位置，第二条是关于这个探测器怎样进行高原探测的一系列说明。位置是由两个整数和一个区分方向的字母组成的，对应了探测器的（x, y）坐标和方向。每个探测器的移动将按序完成，即后一个探测器不能在前一个探测器完成移动之前开始移动。
输出：每个探测器的输出应该是它行进到的最终位置坐标和方向。
输入和输出测试如下。
期待的输入：
5 5
1 2 N
LMLMLMLMM
3 3 E
MMRMMRMRRM
期待的输出：
1 3 N
5 1 E
答案：
程序完整代码如下。
using System;
using System.Collections;
namespace ConsoleApplication5
{
enum Heading {E,S,W,N};
enum X_way {E = 1,S = 0,W = -1,N = 0};
enum Y_way {E = 0,S = -1,W = 0,N = 1};
class Area
{
private static int area_X;
private static int area_Y;
private static ArrayList aryRovers = new ArrayList();
public Area()
{}
protected void AddRover(Rover aRover)
{
aryRovers.Add(aRover);
}
public static bool SetArea(int x, int y)
{
if(area_X == 0 && area_Y == 0)
{
area_X = x;
area_Y = y;
return true;
}
else
return false;
}
public static string GetState()
{
string strTemp = "";
foreach(Rover aobj in aryRovers)
{
strTemp += String.Format("{0} {1} {2} ",
aobj.X,aobj.Y,aobj.heading);
}
return strTemp;
}
public static bool CheckArea(int x,int y)
{
if(x >= 0 && y >= 0 && x <= area_X && y <= area_Y)
return true;
else
return false;
}
}
class Rover:Area
{
protected int m_X;
private int m_Y;
private Heading m_heading;
public int X
{
get
{
return m_X;
}
}
public int Y
{
get
{
return m_Y;
}
}
public Heading heading
{
get
{
return m_heading;
}
}
public Rover(int X_in, int Y_in, Heading heading_in)
{
m_X = X_in;
m_Y = Y_in;
m_heading = heading_in;
AddRover(this);
}
public bool Turnning(bool isLeftTurnning)
{
try
{
m_heading = (Heading)(((int)heading +
(isLeftTurnning?3:1))%4);
return true;
}
catch
{
return false;
}
}
public bool Move()
{
try
{
int x_move = (int)(X_way)(Enum.Parse
(typeof(X_way),m_heading.ToString()));
int y_move = (int)(Y_way)(Enum.Parse
(typeof(Y_way),m_heading.ToString()));
if(CheckArea(m_X + x_move,m_Y + y_move))
{
m_X += x_move;
m_Y += y_move;
}
return true;
}
catch
{
return false;
}
}
}
class Class1
{
/// <summary>
/// 应用程序的主进入点
/// </summary>
[STAThread]
static void Main(string[] args)
{
//
// TODO: 在此加入激活应用程序的代码
//
string strTemp = Console.ReadLine();
try
{
string[]cTemp=strTemp.Trim().Split(new char[]{''});
Area.SetArea(Convert.ToInt32
(cTemp[0]),Convert.ToInt32(cTemp[1]));
}
catch
{
Console.WriteLine("Error...");
}
while((strTemp = Console.ReadLine()).ToUpper() !=
"State".ToUpper())
{
try
{
string[] cTemp = strTemp.Trim().ToUpper().
Split(new char[]{' '});
Rover aRover = new Rover(Convert.ToInt32
(cTemp[0]),Convert.ToInt32(cTemp[1]),
(Heading)Enum.Parse(typeof(Heading),
cTemp[2]));
strTemp = Console.ReadLine().ToUpper();
foreach(char active in strTemp.
ToCharArray())
{
switch(active)
{
case 'L':
aRover.Turnning(true);
break;
case 'R':
aRover.Turnning(false);
break;
case 'M':
aRover.Move();
break;
}
}
}
catch(Exception ex)
{
Console.WriteLine("Error...");
}
}
Console.WriteLine(Area.GetState());
Console.Read();
}
}
}