Codingame : Power of Thor解决思路

心已赠人 2023-07-06 04:49 6阅读 0赞

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80NDE0OTYyNA_size_16_color_FFFFFF_t_70_pic_center]

## 目标 ##

*  达到目标点(lightX, lightY)
 *  不越界
 *  在能量消耗完之前到达

## 原程序 ##

import java.util.*;
    import java.io.*;
    import java.math.*;
    
    /** * Auto-generated code below aims at helping you parse * the standard input according to the problem statement. * --- * Hint: You can use the debug stream to print initialTX and initialTY, if Thor seems not follow your orders. **/
    class Player { 
    
        public static void main(String args[]) { 
            Scanner in = new Scanner(System.in);
            int lightX = in.nextInt(); // the X position of the light of power
            int lightY = in.nextInt(); // the Y position of the light of power
            int initialTx = in.nextInt(); // Thor's starting X position
            int initialTy = in.nextInt(); // Thor's starting Y position
    
            // game loop
            while (true) { 
                int remainingTurns = in.nextInt(); // The remaining amount of turns Thor can move. Do not remove this line.
            
                // Write an action using System.out.println()
                // To debug: System.err.println("Debug messages...");
    
                // A single line providing the move to be made: N NE E SE S SW W or NW
                System.out.println(“SW”);
            }
        }
    }

## 思路 ##

解决方法很简单：只需判断方位拼接字符串就可以了。因为斜向的方位表示："NE NW SE SW "，是以“N”，“S”开头的，因此先判断"Y"轴的方位，再判断“X”轴。

// game loop
    while (true) { 
        int remainingTurns = in.nextInt(); // The remaining amount of turns Thor can move. Do not remove this line.
        String a = "";
        
        if(initialTy < lightY){ 
            a = "S";
        }  
        else if(initialTy > lightY){ 
            a = "N";
        }
        if(initialTx < lightX){ 
            a += "E";
        }
        else if(initialTx > lightX){ 
            a += "W";
        }
           
        // Write an action using System.out.println()
        // To debug: System.err.println("Debug messages...");
    
        // A single line providing the move to be made: N NE E SE S SW W or NW
        System.out.println(a);
    }

### 出错 ###

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80NDE0OTYyNA_size_16_color_FFFFFF_t_70_pic_center 1]  
不过很遗憾，上面代码只能通过单方向移动案例，不能通过需斜对角移动案例。在思路没有错误的情况下，我们去查看输出数据：  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80NDE0OTYyNA_size_16_color_FFFFFF_t_70_pic_center 2]  
数据显示，Thor在最后第二次移动时，Y轴的坐标已经与目标Y坐标相等，但Thor依然“勇往直前”。这就是问题所在。

### 修正 ###

回过头去查看代码，我们发现在while循环中，Thor的坐标从未发送改变，而输出数据“欺骗”了我们，让我们以为变化了（浪费我时间去检查，angry）。

因此我们需要在代码中对Thor的坐标进行操作：

while (true) { 
          int remainingTurns = in.nextInt(); // The remaining amount of turns Thor can move. Do not remove this line.
          String a = "";
          
          if(initialTy < lightY){ 
              initialTy+=1;
              a = "S";
          }  
          else if(initialTy > lightY){ 
              initialTy-=1;
              a = "N";
          }
              
          if(initialTx < lightX){ 
              initialTx +=1;
              a += "E";
          }
              
          else if(initialTx > lightX){ 
              initialTx-=1;
              a += "W";
          }
             
          // Write an action using System.out.println()
          // To debug: System.err.println("Debug messages...");
    
          // A single line providing the move to be made: N NE E SE S SW W or NW
          System.out.println(a);
      }

此时，所有案例通过  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80NDE0OTYyNA_size_16_color_FFFFFF_t_70_pic_center 3]

## 结语 ##

不要尝试枚举所有情况！没有意义

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