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feat: add solutions to lc problem: No.1778
No.1778.Shortest Path in a Hidden Grid
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‎.github/workflows/starcharts.yml

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name: update-starcharts
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on:
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schedule:
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- cron: "0 0/12 * * *"
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workflow_dispatch:
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jobs:
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update-readme:
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name: Generate starcharts
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runs-on: ubuntu-latest
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if: github.repository == 'doocs/leetcode'
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steps:
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- uses: MaoLongLong/actions-starcharts@main
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with:

‎README.md

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## Stars 趋势
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<a href="https://github.com/doocs/leetcode/stargazers" target="_blank"><img src="https://cdn.jsdelivr.net/gh/doocs/leetcode@main/images/starcharts.svg" alt="Stargazers over time" /></a>
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<a href="https://github.com/doocs/leetcode/stargazers" target="_blank"><img src="https://starchart.cc/doocs/leetcode.svg" alt="Stargazers over time" /></a>
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<!-- 这里先使用 https://starchart.cc/ 自动刷新 stars 数据，之后若有问题，可以使用 GitHub Action: starcharts.yml -->
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<!-- <a href="https://github.com/doocs/leetcode/stargazers" target="_blank"><img src="https://cdn.jsdelivr.net/gh/doocs/leetcode@main/images/starcharts.svg" alt="Stargazers over time" /></a> -->
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## 贡献者
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‎README_EN.md

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@@ -157,7 +157,9 @@ You can also contribute to [doocs/leetcode](https://github.com/doocs/leetcode) u
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## Stargazers over time
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<a href="https://github.com/doocs/leetcode/stargazers" target="_blank"><img src="https://cdn.jsdelivr.net/gh/doocs/leetcode@main/images/starcharts.svg" alt="Stargazers over time" /></a>
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<a href="https://github.com/doocs/leetcode/stargazers" target="_blank"><img src="https://starchart.cc/doocs/leetcode.svg" alt="Stargazers over time" /></a>
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<!-- <a href="https://github.com/doocs/leetcode/stargazers" target="_blank"><img src="https://cdn.jsdelivr.net/gh/doocs/leetcode@main/images/starcharts.svg" alt="Stargazers over time" /></a> -->
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## Contributors
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‎solution/1700-1799/1778.Shortest Path in a Hidden Grid/README.md

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Original file line numberDiff line numberDiff line change
@@ -90,22 +90,141 @@ The robot is initially standing on cell (1, 0), denoted by the -1.
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<!-- 这里可写通用的实现逻辑 -->
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**方法一：DFS 建图 + BFS 求最短路**
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相似题目：[1810. 隐藏网格下的最小消耗路径](/solution/1800-1899/1810.Minimum%20Path%20Cost%20in%20a%20Hidden%20Grid/README.md)
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<!-- tabs:start -->
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### **Python3**
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<!-- 这里可写当前语言的特殊实现逻辑 -->
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```python
100-
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# """
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# This is GridMaster's API interface.
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# You should not implement it, or speculate about its implementation
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# """
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# class GridMaster(object):
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# def canMove(self, direction: str) -> bool:
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#
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#
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# def move(self, direction: str) -> bool:
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#
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#
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# def isTarget(self) -> None:
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#
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#
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class Solution(object):
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def findShortestPath(self, master: 'GridMaster') -> int:
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def dfs(i, j):
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nonlocal target
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if master.isTarget():
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target = (i, j)
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for dir, ndir, a, b in dirs:
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x, y = i + a, j + b
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if master.canMove(dir) and (x, y) not in s:
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s.add((x, y))
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master.move(dir)
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dfs(x, y)
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master.move(ndir)
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target = None
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s = set()
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dirs = [['U', 'D', -1, 0], ['D', 'U', 1, 0],
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['L', 'R', 0, -1], ['R', 'L', 0, 1]]
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dfs(0, 0)
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if target is None:
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return -1
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s.remove((0, 0))
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q = deque([(0, 0)])
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ans = -1
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while q:
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ans += 1
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for _ in range(len(q)):
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i, j = q.popleft()
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if (i, j) == target:
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return ans
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for _, _, a, b in dirs:
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x, y = i + a, j + b
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if (x, y) in s:
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s.remove((x, y))
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q.append((x, y))
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return -1
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```
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### **Java**
104158

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<!-- 这里可写当前语言的特殊实现逻辑 -->
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```java
108-
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/**
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* // This is the GridMaster's API interface.
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* // You should not implement it, or speculate about its implementation
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* class GridMaster {
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* boolean canMove(char direction);
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* void move(char direction);
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* boolean isTarget();
169+
* }
170+
*/
171+
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class Solution {
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private static final char[] dir = {'U', 'R', 'D', 'L'};
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private static final char[] ndir = {'D', 'L', 'U', 'R'};
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private static final int[] dirs = {-1, 0, 1, 0, -1};
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private static final int N = 1010;
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private Set<Integer> s;
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private int[] target;
179+
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public int findShortestPath(GridMaster master) {
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target = null;
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s = new HashSet<>();
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s.add(0);
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dfs(0, 0, master);
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if (target == null) {
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return -1;
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}
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s.remove(0);
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Deque<int[]> q = new ArrayDeque<>();
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q.offer(new int[]{0, 0});
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int ans = -1;
192+
while (!q.isEmpty()) {
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++ans;
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for (int n = q.size(); n > 0; --n) {
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int[] p = q.poll();
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int i = p[0], j = p[1];
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if (target[0] == i && target[1] == j) {
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return ans;
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}
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for (int k = 0; k < 4; ++k) {
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int x = i + dirs[k], y = j + dirs[k + 1];
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if (s.contains(x * N + y)) {
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s.remove(x * N + y);
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q.offer(new int[]{x, y});
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}
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}
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}
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}
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return -1;
210+
}
211+
212+
private void dfs(int i, int j, GridMaster master) {
213+
if (master.isTarget()) {
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target = new int[]{i, j};
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}
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for (int k = 0; k < 4; ++k) {
217+
char d = dir[k], nd = ndir[k];
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int x = i + dirs[k], y = j + dirs[k + 1];
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if (master.canMove(d) && !s.contains(x * N + y)) {
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s.add(x * N + y);
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master.move(d);
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dfs(x, y, master);
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master.move(nd);
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}
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}
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}
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}
109228
```
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### **...**

‎solution/1700-1799/1778.Shortest Path in a Hidden Grid/README_EN.md

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Original file line numberDiff line numberDiff line change
@@ -91,13 +91,128 @@ We now know that the target is the cell (0, 1), and the shortest path to the tar
9191
### **Python3**
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```python
94-
94+
# """
95+
# This is GridMaster's API interface.
96+
# You should not implement it, or speculate about its implementation
97+
# """
98+
# class GridMaster(object):
99+
# def canMove(self, direction: str) -> bool:
100+
#
101+
#
102+
# def move(self, direction: str) -> bool:
103+
#
104+
#
105+
# def isTarget(self) -> None:
106+
#
107+
#
108+
109+
class Solution(object):
110+
def findShortestPath(self, master: 'GridMaster') -> int:
111+
def dfs(i, j):
112+
nonlocal target
113+
if master.isTarget():
114+
target = (i, j)
115+
for dir, ndir, a, b in dirs:
116+
x, y = i + a, j + b
117+
if master.canMove(dir) and (x, y) not in s:
118+
s.add((x, y))
119+
master.move(dir)
120+
dfs(x, y)
121+
master.move(ndir)
122+
123+
target = None
124+
s = set()
125+
dirs = [['U', 'D', -1, 0], ['D', 'U', 1, 0],
126+
['L', 'R', 0, -1], ['R', 'L', 0, 1]]
127+
dfs(0, 0)
128+
if target is None:
129+
return -1
130+
s.remove((0, 0))
131+
q = deque([(0, 0)])
132+
ans = -1
133+
while q:
134+
ans += 1
135+
for _ in range(len(q)):
136+
i, j = q.popleft()
137+
if (i, j) == target:
138+
return ans
139+
for _, _, a, b in dirs:
140+
x, y = i + a, j + b
141+
if (x, y) in s:
142+
s.remove((x, y))
143+
q.append((x, y))
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return -1
95145
```
96146

97147
### **Java**
98148

99149
```java
100-
150+
/**
151+
* // This is the GridMaster's API interface.
152+
* // You should not implement it, or speculate about its implementation
153+
* class GridMaster {
154+
* boolean canMove(char direction);
155+
* void move(char direction);
156+
* boolean isTarget();
157+
* }
158+
*/
159+
160+
class Solution {
161+
private static final char[] dir = {'U', 'R', 'D', 'L'};
162+
private static final char[] ndir = {'D', 'L', 'U', 'R'};
163+
private static final int[] dirs = {-1, 0, 1, 0, -1};
164+
private static final int N = 1010;
165+
private Set<Integer> s;
166+
private int[] target;
167+
168+
public int findShortestPath(GridMaster master) {
169+
target = null;
170+
s = new HashSet<>();
171+
s.add(0);
172+
dfs(0, 0, master);
173+
if (target == null) {
174+
return -1;
175+
}
176+
s.remove(0);
177+
Deque<int[]> q = new ArrayDeque<>();
178+
q.offer(new int[]{0, 0});
179+
int ans = -1;
180+
while (!q.isEmpty()) {
181+
++ans;
182+
for (int n = q.size(); n > 0; --n) {
183+
int[] p = q.poll();
184+
int i = p[0], j = p[1];
185+
if (target[0] == i && target[1] == j) {
186+
return ans;
187+
}
188+
for (int k = 0; k < 4; ++k) {
189+
int x = i + dirs[k], y = j + dirs[k + 1];
190+
if (s.contains(x * N + y)) {
191+
s.remove(x * N + y);
192+
q.offer(new int[]{x, y});
193+
}
194+
}
195+
}
196+
}
197+
return -1;
198+
}
199+
200+
private void dfs(int i, int j, GridMaster master) {
201+
if (master.isTarget()) {
202+
target = new int[]{i, j};
203+
}
204+
for (int k = 0; k < 4; ++k) {
205+
char d = dir[k], nd = ndir[k];
206+
int x = i + dirs[k], y = j + dirs[k + 1];
207+
if (master.canMove(d) && !s.contains(x * N + y)) {
208+
s.add(x * N + y);
209+
master.move(d);
210+
dfs(x, y, master);
211+
master.move(nd);
212+
}
213+
}
214+
}
215+
}
101216
```
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### **...**

‎solution/1700-1799/1778.Shortest Path in a Hidden Grid/Solution.java

+66
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@@ -0,0 +1,66 @@
1+
/**
2+
* // This is the GridMaster's API interface.
3+
* // You should not implement it, or speculate about its implementation
4+
* class GridMaster {
5+
* boolean canMove(char direction);
6+
* void move(char direction);
7+
* boolean isTarget();
8+
* }
9+
*/
10+
11+
class Solution {
12+
private static final char[] dir = {'U', 'R', 'D', 'L'};
13+
private static final char[] ndir = {'D', 'L', 'U', 'R'};
14+
private static final int[] dirs = {-1, 0, 1, 0, -1};
15+
private static final int N = 1010;
16+
private Set<Integer> s;
17+
private int[] target;
18+
19+
public int findShortestPath(GridMaster master) {
20+
target = null;
21+
s = new HashSet<>();
22+
s.add(0);
23+
dfs(0, 0, master);
24+
if (target == null) {
25+
return -1;
26+
}
27+
s.remove(0);
28+
Deque<int[]> q = new ArrayDeque<>();
29+
q.offer(new int[]{0, 0});
30+
int ans = -1;
31+
while (!q.isEmpty()) {
32+
++ans;
33+
for (int n = q.size(); n > 0; --n) {
34+
int[] p = q.poll();
35+
int i = p[0], j = p[1];
36+
if (target[0] == i && target[1] == j) {
37+
return ans;
38+
}
39+
for (int k = 0; k < 4; ++k) {
40+
int x = i + dirs[k], y = j + dirs[k + 1];
41+
if (s.contains(x * N + y)) {
42+
s.remove(x * N + y);
43+
q.offer(new int[]{x, y});
44+
}
45+
}
46+
}
47+
}
48+
return -1;
49+
}
50+
51+
private void dfs(int i, int j, GridMaster master) {
52+
if (master.isTarget()) {
53+
target = new int[]{i, j};
54+
}
55+
for (int k = 0; k < 4; ++k) {
56+
char d = dir[k], nd = ndir[k];
57+
int x = i + dirs[k], y = j + dirs[k + 1];
58+
if (master.canMove(d) && !s.contains(x * N + y)) {
59+
s.add(x * N + y);
60+
master.move(d);
61+
dfs(x, y, master);
62+
master.move(nd);
63+
}
64+
}
65+
}
66+
}

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