add 0117 Java and Python

This commit is contained in:
KaiserTT
2024-07-01 13:06:09 +08:00
parent 918590614e
commit 2b93089f56

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@ -167,7 +167,7 @@
![](https://code-thinking-1253855093.file.myqcloud.com/pics/20240510114004.png)
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后面的过程一样的节点3 和 节点4入度都为0选哪个都行。
@ -344,8 +344,107 @@ int main() {
### Java
```java
import java.util.*;
public class Main {
public static void main(String[] args) {
Scanner scanner = new Scanner(System.in);
int n = scanner.nextInt();
int m = scanner.nextInt();
List<List<Integer>> umap = new ArrayList<>(); // 记录文件依赖关系
int[] inDegree = new int[n]; // 记录每个文件的入度
for (int i = 0; i < n; i++)
umap.add(new ArrayList<>());
for (int i = 0; i < m; i++) {
int s = scanner.nextInt();
int t = scanner.nextInt();
umap.get(s).add(t); // 记录s指向哪些文件
inDegree[t]++; // t的入度加一
}
Queue<Integer> queue = new LinkedList<>();
for (int i = 0; i < n; i++) {
if (inDegree[i] == 0) {
// 入度为0的文件可以作为开头先加入队列
queue.add(i);
}
}
List<Integer> result = new ArrayList<>();
// 拓扑排序
while (!queue.isEmpty()) {
int cur = queue.poll(); // 当前选中的文件
result.add(cur);
for (int file : umap.get(cur)) {
inDegree[file]--; // cur的指向的文件入度-1
if (inDegree[file] == 0) {
queue.add(file);
}
}
}
if (result.size() == n) {
for (int i = 0; i < result.size(); i++) {
System.out.print(result.get(i));
if (i < result.size() - 1) {
System.out.print(" ");
}
}
} else {
System.out.println(-1);
}
}
}
```
### Python
```python
from collections import deque, defaultdict
def topological_sort(n, edges):
inDegree = [0] * n # inDegree 记录每个文件的入度
umap = defaultdict(list) # 记录文件依赖关系
# 构建图和入度表
for s, t in edges:
inDegree[t] += 1
umap[s].append(t)
# 初始化队列加入所有入度为0的节点
queue = deque([i for i in range(n) if inDegree[i] == 0])
result = []
while queue:
cur = queue.popleft() # 当前选中的文件
result.append(cur)
for file in umap[cur]: # 获取该文件指向的文件
inDegree[file] -= 1 # cur的指向的文件入度-1
if inDegree[file] == 0:
queue.append(file)
if len(result) == n:
print(" ".join(map(str, result)))
else:
print(-1)
if __name__ == "__main__":
n, m = map(int, input().split())
edges = [tuple(map(int, input().split())) for _ in range(m)]
topological_sort(n, edges)
```
### Go
### Rust