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feat: add solutions to lc problem: No.1273
No.1273.Delete Tree Nodes
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-4
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‎solution/0700-0799/0742.Closest Leaf in a Binary Tree/README.md

+3-1
Original file line numberDiff line numberDiff line change
@@ -74,7 +74,9 @@ root = [1,2,3,4,null,null,null,5,null,6], k = 2
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<!-- 这里可写通用的实现逻辑 -->
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DFS。
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DFS 和 BFS。
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先通过 DFS 构建图，然后 BFS 找距离值为 k 的结点最近的叶子结点。
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<!-- tabs:start -->
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‎solution/0700-0799/0742.Closest Leaf in a Binary Tree/README_EN.md

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@@ -120,7 +120,7 @@ Diagram of binary tree:
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## Solutions
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DFS.
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DFS & BFS.
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<!-- tabs:start -->
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‎solution/1200-1299/1273.Delete Tree Nodes/README.md

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Original file line numberDiff line numberDiff line change
@@ -64,22 +64,134 @@
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<!-- 这里可写通用的实现逻辑 -->
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先构建图。
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然后对于树中的每一个节点 u，我们通过深度优先搜索的方法，递归地搜索它的所有子节点 v，计算出以 v 为根的子树的节点数目和权值之和。在这之后，我们将子节点的值分别进行累加，就可以得到以 u 为根的子树的节点数目和权值之和。如果权值之和为零，那么以 u 为根的子树需要被删除，我们将其节点数目也置为零，作为结果返回到上一层。最终根节点 0 对应的节点数目即为答案。
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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
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class Solution:
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def deleteTreeNodes(self, nodes: int, parent: List[int], value: List[int]) -> int:
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def dfs(u):
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for v in g[u]:
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dfs(v)
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value[u] += value[v]
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counter[u] += counter[v]
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if value[u] == 0:
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counter[u] = 0
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g = defaultdict(list)
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for i, p in enumerate(parent):
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if p != -1:
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g[p].append(i)
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counter = [1] * nodes
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dfs(0)
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return counter[0]
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```
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### **Java**
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<!-- 这里可写当前语言的特殊实现逻辑 -->
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```java
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class Solution {
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private Map<Integer, List<Integer>> g;
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private int[] counter;
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private int[] value;
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public int deleteTreeNodes(int nodes, int[] parent, int[] value) {
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g = new HashMap<>();
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for (int i = 0; i < nodes; ++i) {
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if (parent[i] != -1) {
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g.computeIfAbsent(parent[i], k -> new ArrayList<>()).add(i);
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}
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}
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this.value = value;
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counter = new int[nodes];
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Arrays.fill(counter, 1);
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dfs(0);
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return counter[0];
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}
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private void dfs(int u) {
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for (int v : g.getOrDefault(u, Collections.emptyList())) {
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dfs(v);
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value[u] += value[v];
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counter[u] += counter[v];
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}
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if (value[u] == 0) {
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counter[u] = 0;
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}
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}
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}
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```
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### **C++**
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```cpp
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class Solution {
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public:
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unordered_map<int, vector<int>> g;
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vector<int> counter;
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vector<int> value;
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int deleteTreeNodes(int nodes, vector<int>& parent, vector<int>& value) {
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for (int i = 0; i < nodes; ++i)
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if (parent[i] != -1)
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g[parent[i]].push_back(i);
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counter.resize(nodes, 1);
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this->value = value;
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dfs(0);
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return counter[0];
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}
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void dfs(int u) {
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for (int v : g[u])
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{
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dfs(v);
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value[u] += value[v];
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counter[u] += counter[v];
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}
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if (value[u] == 0) counter[u] = 0;
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}
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};
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```
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### **Go**
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```go
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func deleteTreeNodes(nodes int, parent []int, value []int) int {
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g := make(map[int][]int)
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for i, p := range parent {
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if p != -1 {
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g[p] = append(g[p], i)
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}
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}
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counter := make([]int, nodes)
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for i := range counter {
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counter[i] = 1
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}
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var dfs func(u int)
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dfs = func(u int) {
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if vs, ok := g[u]; ok {
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for _, v := range vs {
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dfs(v)
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value[u] += value[v]
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counter[u] += counter[v]
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}
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}
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if value[u] == 0 {
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counter[u] = 0
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}
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}
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dfs(0)
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return counter[0]
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}
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```
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### **...**

‎solution/1200-1299/1273.Delete Tree Nodes/README_EN.md

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Original file line numberDiff line numberDiff line change
@@ -65,13 +65,121 @@
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### **Python3**
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```python
68-
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class Solution:
69+
def deleteTreeNodes(self, nodes: int, parent: List[int], value: List[int]) -> int:
70+
def dfs(u):
71+
for v in g[u]:
72+
dfs(v)
73+
value[u] += value[v]
74+
counter[u] += counter[v]
75+
if value[u] == 0:
76+
counter[u] = 0
77+
78+
g = defaultdict(list)
79+
for i, p in enumerate(parent):
80+
if p != -1:
81+
g[p].append(i)
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counter = [1] * nodes
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dfs(0)
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return counter[0]
6985
```
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### **Java**
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```java
90+
class Solution {
91+
private Map<Integer, List<Integer>> g;
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private int[] counter;
93+
private int[] value;
94+
95+
public int deleteTreeNodes(int nodes, int[] parent, int[] value) {
96+
g = new HashMap<>();
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for (int i = 0; i < nodes; ++i) {
98+
if (parent[i] != -1) {
99+
g.computeIfAbsent(parent[i], k -> new ArrayList<>()).add(i);
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}
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}
102+
this.value = value;
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counter = new int[nodes];
104+
Arrays.fill(counter, 1);
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dfs(0);
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return counter[0];
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}
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private void dfs(int u) {
110+
for (int v : g.getOrDefault(u, Collections.emptyList())) {
111+
dfs(v);
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value[u] += value[v];
113+
counter[u] += counter[v];
114+
}
115+
if (value[u] == 0) {
116+
counter[u] = 0;
117+
}
118+
}
119+
}
120+
```
121+
122+
### **C++**
123+
124+
```cpp
125+
class Solution {
126+
public:
127+
unordered_map<int, vector<int>> g;
128+
vector<int> counter;
129+
vector<int> value;
130+
131+
int deleteTreeNodes(int nodes, vector<int>& parent, vector<int>& value) {
132+
for (int i = 0; i < nodes; ++i)
133+
if (parent[i] != -1)
134+
g[parent[i]].push_back(i);
135+
counter.resize(nodes, 1);
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this->value = value;
137+
dfs(0);
138+
return counter[0];
139+
}
140+
141+
void dfs(int u) {
142+
for (int v : g[u])
143+
{
144+
dfs(v);
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value[u] += value[v];
146+
counter[u] += counter[v];
147+
}
148+
if (value[u] == 0) counter[u] = 0;
149+
}
150+
};
151+
```
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### **Go**
154+
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```go
156+
func deleteTreeNodes(nodes int, parent []int, value []int) int {
157+
g := make(map[int][]int)
158+
for i, p := range parent {
159+
if p != -1 {
160+
g[p] = append(g[p], i)
161+
}
162+
}
163+
counter := make([]int, nodes)
164+
for i := range counter {
165+
counter[i] = 1
166+
}
167+
var dfs func(u int)
168+
dfs = func(u int) {
169+
if vs, ok := g[u]; ok {
170+
for _, v := range vs {
171+
dfs(v)
172+
value[u] += value[v]
173+
counter[u] += counter[v]
174+
}
175+
}
176+
if value[u] == 0 {
177+
counter[u] = 0
178+
}
179+
}
180+
dfs(0)
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return counter[0]
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}
75183
```
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77185
### **...**

‎solution/1200-1299/1273.Delete Tree Nodes/Solution.cpp

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Original file line numberDiff line numberDiff line change
@@ -0,0 +1,26 @@
1+
class Solution {
2+
public:
3+
unordered_map<int, vector<int>> g;
4+
vector<int> counter;
5+
vector<int> value;
6+
7+
int deleteTreeNodes(int nodes, vector<int>& parent, vector<int>& value) {
8+
for (int i = 0; i < nodes; ++i)
9+
if (parent[i] != -1)
10+
g[parent[i]].push_back(i);
11+
counter.resize(nodes, 1);
12+
this->value = value;
13+
dfs(0);
14+
return counter[0];
15+
}
16+
17+
void dfs(int u) {
18+
for (int v : g[u])
19+
{
20+
dfs(v);
21+
value[u] += value[v];
22+
counter[u] += counter[v];
23+
}
24+
if (value[u] == 0) counter[u] = 0;
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}
26+
};

‎solution/1200-1299/1273.Delete Tree Nodes/Solution.go

+27
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,27 @@
1+
func deleteTreeNodes(nodes int, parent []int, value []int) int {
2+
g := make(map[int][]int)
3+
for i, p := range parent {
4+
if p != -1 {
5+
g[p] = append(g[p], i)
6+
}
7+
}
8+
counter := make([]int, nodes)
9+
for i := range counter {
10+
counter[i] = 1
11+
}
12+
var dfs func(u int)
13+
dfs = func(u int) {
14+
if vs, ok := g[u]; ok {
15+
for _, v := range vs {
16+
dfs(v)
17+
value[u] += value[v]
18+
counter[u] += counter[v]
19+
}
20+
}
21+
if value[u] == 0 {
22+
counter[u] = 0
23+
}
24+
}
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dfs(0)
26+
return counter[0]
27+
}

‎solution/1200-1299/1273.Delete Tree Nodes/Solution.java

+30
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,30 @@
1+
class Solution {
2+
private Map<Integer, List<Integer>> g;
3+
private int[] counter;
4+
private int[] value;
5+
6+
public int deleteTreeNodes(int nodes, int[] parent, int[] value) {
7+
g = new HashMap<>();
8+
for (int i = 0; i < nodes; ++i) {
9+
if (parent[i] != -1) {
10+
g.computeIfAbsent(parent[i], k -> new ArrayList<>()).add(i);
11+
}
12+
}
13+
this.value = value;
14+
counter = new int[nodes];
15+
Arrays.fill(counter, 1);
16+
dfs(0);
17+
return counter[0];
18+
}
19+
20+
private void dfs(int u) {
21+
for (int v : g.getOrDefault(u, Collections.emptyList())) {
22+
dfs(v);
23+
value[u] += value[v];
24+
counter[u] += counter[v];
25+
}
26+
if (value[u] == 0) {
27+
counter[u] = 0;
28+
}
29+
}
30+
}

‎solution/1200-1299/1273.Delete Tree Nodes/Solution.py

+17
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,17 @@
1+
class Solution:
2+
def deleteTreeNodes(self, nodes: int, parent: List[int], value: List[int]) -> int:
3+
def dfs(u):
4+
for v in g[u]:
5+
dfs(v)
6+
value[u] += value[v]
7+
counter[u] += counter[v]
8+
if value[u] == 0:
9+
counter[u] = 0
10+
11+
g = defaultdict(list)
12+
for i, p in enumerate(parent):
13+
if p != -1:
14+
g[p].append(i)
15+
counter = [1] * nodes
16+
dfs(0)
17+
return counter[0]

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