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Commit b04d7fe

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feat: add solutions to lc problem: No.0547.Number of Provinces
1 parent 14c5a12 commit b04d7fe

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‎solution/0500-0599/0547.Number of Provinces/README.md‎

Lines changed: 194 additions & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -52,14 +52,70 @@
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<!-- 这里可写通用的实现逻辑 -->
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55-
深度优先搜索。判断学生与学生之间是否属于同一个连通分量,最后连通分量的总数即为结果。
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**方法一:深度优先搜索**
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判断学生与学生之间是否属于同一个连通分量,最后连通分量的总数即为结果。
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**方法二:并查集**
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模板 1——朴素并查集:
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```python
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# 初始化,p存储每个点的祖宗节点
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p = [i for i in range(n)]
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# 返回x的祖宗节点
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def find(x):
68+
if p[x] != x:
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# 路径压缩
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p[x] = find(p[x])
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return p[x]
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# 合并a和b所在的两个集合
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p[find(a)] = find(b)
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```
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模板 2——维护 size 的并查集:
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```python
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# 初始化,p存储每个点的祖宗节点,size只有当节点是祖宗节点时才有意义,表示祖宗节点所在集合中,点的数量
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p = [i for i in range(n)]
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size = [1] * n
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# 返回x的祖宗节点
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def find(x):
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if p[x] != x:
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# 路径压缩
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p[x] = find(p[x])
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return p[x]
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# 合并a和b所在的两个集合
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size[find(b)] += size[find(a)]
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p[find(a)] = find(b)
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```
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模板 3——维护到祖宗节点距离的并查集:
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```python
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# 初始化,p存储每个点的祖宗节点,d[x]存储x到p[x]的距离
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p = [i for i in range(n)]
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d = [0] * n
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# 返回x的祖宗节点
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def find(x):
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if p[x] != x:
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t = find(p[x])
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d[x] += d[p[x]]
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p[x] = t
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return p[x]
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# 合并a和b所在的两个集合
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p[find(a)] = find(b)
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d[find(a)] = dinstance
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```
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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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深度优先搜索:
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```python
64120
class Solution:
65121
def findCircleNum(self, isConnected: List[List[int]]) -> int:
@@ -79,10 +135,32 @@ class Solution:
79135
return num
80136
```
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并查集:
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```python
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class Solution:
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def findCircleNum(self, isConnected: List[List[int]]) -> int:
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n = len(isConnected)
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p = [i for i in range(n)]
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def find(x):
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if p[x] != x:
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p[x] = find(p[x])
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return p[x]
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for i in range(n):
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for j in range(n):
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if i != j and isConnected[i][j] == 1:
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p[find(i)] = find(j)
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return sum(i == find(i) for i in range(n))
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```
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82158
### **Java**
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84160
<!-- 这里可写当前语言的特殊实现逻辑 -->
85161

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深度优先搜索:
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86164
```java
87165
class Solution {
88166
public int findCircleNum(int[][] isConnected) {
@@ -109,6 +187,121 @@ class Solution {
109187
}
110188
```
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并查集:
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```java
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class Solution {
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private int[] p;
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public int findCircleNum(int[][] isConnected) {
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int n = isConnected.length;
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p = new int[n];
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for (int i = 0; i < n; ++i) {
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p[i] = i;
201+
}
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for (int i = 0; i < n; ++i) {
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for (int j = 0; j < n; ++j) {
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if (isConnected[i][j] == 1) {
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p[find(i)] = find(j);
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}
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}
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}
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int cnt = 0;
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for (int i = 0; i < n; ++i) {
211+
if (i == find(i)) {
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++cnt;
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}
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}
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return cnt;
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}
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private int find(int x) {
219+
if (p[x] != x) {
220+
p[x] = find(p[x]);
221+
}
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return p[x];
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}
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}
225+
```
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### **C++**
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```cpp
230+
class Solution {
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public:
232+
vector<int> p;
233+
234+
int findCircleNum(vector<vector<int>> &isConnected) {
235+
int n = isConnected.size();
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p.resize(n);
237+
for (int i = 0; i < n; ++i)
238+
{
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p[i] = i;
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}
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for (int i = 0; i < n; ++i)
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{
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for (int j = 0; j < n; ++j)
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{
245+
if (isConnected[i][j])
246+
{
247+
p[find(i)] = find(j);
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}
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}
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}
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int cnt = 0;
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for (int i = 0; i < n; ++i)
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{
254+
if (i == find(i))
255+
++cnt;
256+
}
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return cnt;
258+
}
259+
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int find(int x) {
261+
if (p[x] != x)
262+
{
263+
p[x] = find(p[x]);
264+
}
265+
return p[x];
266+
}
267+
};
268+
```
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### **Go**
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```go
273+
var p []int
274+
275+
func findCircleNum(isConnected [][]int) int {
276+
n := len(isConnected)
277+
p = make([]int, n)
278+
for i := 1; i < n; i++ {
279+
p[i] = i
280+
}
281+
for i := 0; i < n; i++ {
282+
for j := 0; j < n; j++ {
283+
if isConnected[i][j] == 1 {
284+
p[find(i)] = find(j)
285+
}
286+
}
287+
}
288+
cnt := 0
289+
for i := 0; i < n; i++ {
290+
if i == find(i) {
291+
cnt++
292+
}
293+
}
294+
return cnt
295+
}
296+
297+
func find(x int) int {
298+
if p[x] != x {
299+
p[x] = find(p[x])
300+
}
301+
return p[x]
302+
}
303+
```
304+
112305
### **...**
113306

114307
```

‎solution/0500-0599/0547.Number of Provinces/README_EN.md‎

Lines changed: 131 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -65,6 +65,24 @@ class Solution:
6565
return num
6666
```
6767

68+
```python
69+
class Solution:
70+
def findCircleNum(self, isConnected: List[List[int]]) -> int:
71+
n = len(isConnected)
72+
p = [i for i in range(n)]
73+
74+
def find(x):
75+
if p[x] != x:
76+
p[x] = find(p[x])
77+
return p[x]
78+
79+
for i in range(n):
80+
for j in range(n):
81+
if i != j and isConnected[i][j] == 1:
82+
p[find(i)] = find(j)
83+
return sum(i == find(i) for i in range(n))
84+
```
85+
6886
### **Java**
6987

7088
```java
@@ -93,6 +111,119 @@ class Solution {
93111
}
94112
```
95113

114+
```java
115+
class Solution {
116+
private int[] p;
117+
118+
public int findCircleNum(int[][] isConnected) {
119+
int n = isConnected.length;
120+
p = new int[n];
121+
for (int i = 0; i < n; ++i) {
122+
p[i] = i;
123+
}
124+
for (int i = 0; i < n; ++i) {
125+
for (int j = 0; j < n; ++j) {
126+
if (isConnected[i][j] == 1) {
127+
p[find(i)] = find(j);
128+
}
129+
}
130+
}
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int cnt = 0;
132+
for (int i = 0; i < n; ++i) {
133+
if (i == find(i)) {
134+
++cnt;
135+
}
136+
}
137+
return cnt;
138+
}
139+
140+
private int find(int x) {
141+
if (p[x] != x) {
142+
p[x] = find(p[x]);
143+
}
144+
return p[x];
145+
}
146+
}
147+
```
148+
149+
### **C++**
150+
151+
```cpp
152+
class Solution {
153+
public:
154+
vector<int> p;
155+
156+
int findCircleNum(vector<vector<int>> &isConnected) {
157+
int n = isConnected.size();
158+
p.resize(n);
159+
for (int i = 0; i < n; ++i)
160+
{
161+
p[i] = i;
162+
}
163+
for (int i = 0; i < n; ++i)
164+
{
165+
for (int j = 0; j < n; ++j)
166+
{
167+
if (isConnected[i][j])
168+
{
169+
p[find(i)] = find(j);
170+
}
171+
}
172+
}
173+
int cnt = 0;
174+
for (int i = 0; i < n; ++i)
175+
{
176+
if (i == find(i))
177+
++cnt;
178+
}
179+
return cnt;
180+
}
181+
182+
int find(int x) {
183+
if (p[x] != x)
184+
{
185+
p[x] = find(p[x]);
186+
}
187+
return p[x];
188+
}
189+
};
190+
```
191+
192+
### **Go**
193+
194+
```go
195+
var p []int
196+
197+
func findCircleNum(isConnected [][]int) int {
198+
n := len(isConnected)
199+
p = make([]int, n)
200+
for i := 1; i < n; i++ {
201+
p[i] = i
202+
}
203+
for i := 0; i < n; i++ {
204+
for j := 0; j < n; j++ {
205+
if isConnected[i][j] == 1 {
206+
p[find(i)] = find(j)
207+
}
208+
}
209+
}
210+
cnt := 0
211+
for i := 0; i < n; i++ {
212+
if i == find(i) {
213+
cnt++
214+
}
215+
}
216+
return cnt
217+
}
218+
219+
func find(x int) int {
220+
if p[x] != x {
221+
p[x] = find(p[x])
222+
}
223+
return p[x]
224+
}
225+
```
226+
96227
### **...**
97228

98229
```

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