C++程序:找出二维平面中从一个点到另一个点的移动路径


假设在二维平面中有两个点a和b,它们的坐标分别为(x1, y1)和(x2, y2)。目前我们位于点'a',并且每次只能垂直或水平移动一个单位距离。我们需要从点'a'移动到点'b',再返回点'a',最后再次移动到点'b'。除了点a和b之外,不允许经过相同的点多次。我们需要找出整个行程中所做的移动,并输出结果。如果向右移动,则输出'R',向左移动则输出'L',向上移动则输出'U',向下移动则输出'D'。需要注意的是,x2 > x1 且 y2 > y1。

例如,如果输入x1 = 0,y1 = 1,x2 = 3,y2 = 4,则输出将为UUURRRDDDLLLLUUUURRRRDRDDDDLLLLU

为了解决这个问题,我们将遵循以下步骤:

s := a blank string
for initialize i := 0, when i < y2 - y1, update (increase i by 1), do:
   add "U" at the end of s
for initialize i := 0, when i < x2 - x1, update (increase i by 1), do:
   add "R" at the end of s
for initialize i := 0, when i < y2 - y1, update (increase i by 1), do:
   add "D" at the end of s
for initialize i := 0, when i < x2 - x1, update (increase i by 1), do:
   add "L" at the end of s
   add "LU" at the end of s
for initialize i := 0, when i < y2 - y1, update (increase i by 1), do:
   add "U" at the end of s
for initialize i := 0, when i < x2 - x1, update (increase i by 1), do:
   add "R" at the end of s
   add "RD" at the end of s
   add "RD" at the end of s
for initialize i := 0, when i < y2 - y1, update (increase i by 1), do:
   add "D" at the end of s
for initialize i := 0, when i < x2 - x1, update (increase i by 1), do:
   add "L" at the end of s
   add "LU" at the end of s
return s

示例

让我们来看下面的实现,以便更好地理解:

#include <bits/stdc++.h>
using namespace std;

string solve(int x1, int y1, int x2, int y2){
   string s = "";
   for(int i = 0; i < y2 - y1; i++)
      s.append("U");
   for(int i = 0; i < x2 - x1; i++)
      s.append("R");
   for(int i = 0; i < y2 - y1; i++)
      s.append("D");
   for(int i = 0; i < x2 - x1; i++)
      s.append("L");
   s.append("LU");
   for(int i = 0; i < y2 - y1; i++)
      s.append("U");
   for(int i = 0; i < x2 - x1; i++)
      s.append("R");
      s.append("RD");
      s.append("RD");
   for(int i = 0; i < y2 - y1; i++)  
      s.append("D");
   for(int i = 0; i < x2 - x1; i++) s.append("L");
      s.append("LU");
   return s;
}
int main() {
   int x1 = 0, y1 = 1, x2 = 3, y2 = 4; cout<< solve(x1, y1, x2, y2);
   return 0;
}

输入

0, 1, 3, 4

输出

UUURRRDDDLLLLUUUURRRRDRDDDDLLLLU

更新于: 2022年3月2日

245 次浏览

开启你的 职业生涯

通过完成课程获得认证

开始学习
广告