From fed25bf0125118e4b985fb58d122430b3141b919 Mon Sep 17 00:00:00 2001 From: suinming <0223314338aa@gmail.com> Date: Sat, 21 Sep 2024 14:36:45 +0800 Subject: [PATCH 1/5] =?UTF-8?q?feat:=20=E5=9C=96=E8=AB=96100=E5=B2=9B?= =?UTF-8?q?=E5=B1=BF=E7=9A=84=E6=9C=80=E5=A4=A7=E9=9D=A2=E7=A7=AF=EF=BC=8C?= =?UTF-8?q?=E6=96=B0=E5=A2=9Ejs=E6=B7=B1=E6=90=9C=E7=AE=97=E6=B3=95?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- .../kamacoder/0100.岛屿的最大面积.md | 77 +++++++++++++++++++ 1 file changed, 77 insertions(+) diff --git a/problems/kamacoder/0100.岛屿的最大面积.md b/problems/kamacoder/0100.岛屿的最大面积.md index ea62edc2..51bfc57f 100644 --- a/problems/kamacoder/0100.岛屿的最大面积.md +++ b/problems/kamacoder/0100.岛屿的最大面积.md @@ -480,7 +480,84 @@ const bfs = (graph, visited, x, y) => { })() ``` +```javascript +// 深搜版 + +const r1 = require('readline').createInterface({ input: process.stdin }); +// 创建readline接口 +let iter = r1[Symbol.asyncIterator](); +// 创建异步迭代器 +const readline = async () => (await iter.next()).value; + +let graph // 地图 +let N, M // 地图大小 +let visited // 访问过的节点 +let result = 0 // 最大岛屿面积 +let count = 0 // 岛屿内节点数 +const dir = [[0, 1], [1, 0], [0, -1], [-1, 0]] //方向 + +// 读取输入，初始化地图 +const initGraph = async () => { + let line = await readline(); + [N, M] = line.split(' ').map(Number); + graph = new Array(N).fill(0).map(() => new Array(M).fill(0)) + visited = new Array(N).fill(false).map(() => new Array(M).fill(false)) + + for (let i = 0; i < N; i++) { + line = await readline() + line = line.split(' ').map(Number) + for (let j = 0; j < M; j++) { + graph[i][j] = line[j] + } + } +} + +/** + * @description: 从(x, y)开始深度优先遍历 + * @param {*} graph 地图 + * @param {*} visited 访问过的节点 + * @param {*} x 开始搜索节点的下标 + * @param {*} y 开始搜索节点的下标 + * @return {*} + */ +const dfs = (graph, visited, x, y) => { + for (let i = 0; i < 4; i++) { + let nextx = x + dir[i][0] + let nexty = y + dir[i][1] + if(nextx < 0 || nextx >= N || nexty < 0 || nexty >= M) continue + if(!visited[nextx][nexty] && graph[nextx][nexty] === 1){ + count++ + visited[nextx][nexty] = true + dfs(graph, visited, nextx, nexty) + } + } +} + +(async function () { + + // 读取输入，初始化地图 + await initGraph() + + // 统计最大岛屿面积 + for (let i = 0; i < N; i++) { + for (let j = 0; j < M; j++) { + if (!visited[i][j] && graph[i][j] === 1) { //遇到没有访问过的陆地 + // 重新计算面积 + count = 1 + visited[i][j] = true + + // 深度优先遍历，统计岛屿内节点数，并将岛屿标记为已访问 + dfs(graph, visited, i, j) + + // 更新最大岛屿面积 + result = Math.max(result, count) + } + } + } + console.log(result); +})() +``` ### TypeScript From 99e85bfea1804fcc87458d858fed44d76c7996f2 Mon Sep 17 00:00:00 2001 From: suinming <0223314338aa@gmail.com> Date: Sat, 21 Sep 2024 16:05:46 +0800 Subject: [PATCH 2/5] =?UTF-8?q?feat:=20=E5=9C=96=E8=AB=96101=E5=AD=A4?= =?UTF-8?q?=E5=B3=B6=E6=80=BB=E9=9D=A2=E7=A7=AF=20=EF=BC=8C=E6=96=B0?= =?UTF-8?q?=E5=A2=9Epython=E6=B7=B1=E6=90=9C=E7=AE=97=E6=B3=95?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- problems/kamacoder/0101.孤岛的总面积.md | 65 +++++++++++++++++++ 1 file changed, 65 insertions(+) diff --git a/problems/kamacoder/0101.孤岛的总面积.md b/problems/kamacoder/0101.孤岛的总面积.md index 006484de..26c92c07 100644 --- a/problems/kamacoder/0101.孤岛的总面积.md +++ b/problems/kamacoder/0101.孤岛的总面积.md @@ -307,6 +307,71 @@ for i in range(n): print(count) ``` + +```python +direction = [[1, 0], [-1, 0], [0, 1], [0, -1]] +result = 0 + +# 深度搜尋 +def dfs(grid, y, x): + grid[y][x] = 0 + global result + result += 1 + + for i, j in direction: + next_x = x + j + next_y = y + i + if (next_x < 0 or next_y < 0 or + next_x >= len(grid[0]) or next_y >= len(grid) + ): + continue + if grid[next_y][next_x] == 1 and not visited[next_y][next_x]: + visited[next_y][next_x] = True + dfs(grid, next_y, next_x) + + +# 讀取輸入值 +n, m = map(int, input().split()) +grid = [] +visited = [[False] * m for _ in range(n)] + +for i in range(n): + grid.append(list(map(int, input().split()))) + +# 處理邊界 +for j in range(m): + # 上邊界 + if grid[0][j] == 1 and not visited[0][j]: + visited[0][j] = True + dfs(grid, 0, j) + # 下邊界 + if grid[n - 1][j] == 1 and not visited[n - 1][j]: + visited[n - 1][j] = True + dfs(grid, n - 1, j) + +for i in range(n): + # 左邊界 + if grid[i][0] == 1 and not visited[i][0]: + visited[i][0] = True + dfs(grid, i, 0) + # 右邊界 + if grid[i][m - 1] == 1 and not visited[i][m - 1]: + visited[i][m - 1] = True + dfs(grid, i, m - 1) + +# 計算孤島總面積 +result = 0 # 初始化，避免使用到處理邊界時所產生的累加值 + +for i in range(n): + for j in range(m): + if grid[i][j] == 1 and not visited[i][j]: + visited[i][j] = True + dfs(grid, i, j) + +# 輸出孤島的總面積 +print(result) +``` + ### Go ``` go From 848fbd4cd5c868839c75c637ef5ea9057ab301d7 Mon Sep 17 00:00:00 2001 From: Zhihan Li <54661071+zhihali@users.noreply.github.com> Date: Sun, 22 Sep 2024 16:22:04 +0100 Subject: [PATCH 3/5] =?UTF-8?q?Update=200053.=E6=9C=80=E5=A4=A7=E5=AD=90?= =?UTF-8?q?=E5=BA=8F=E5=92=8C.md?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- problems/0053.最大子序和.md | 15 +++++++++++++-- 1 file changed, 13 insertions(+), 2 deletions(-) diff --git a/problems/0053.最大子序和.md b/problems/0053.最大子序和.md index 551c39bf..1c7ff0cd 100644 --- a/problems/0053.最大子序和.md +++ b/problems/0053.最大子序和.md @@ -214,6 +214,7 @@ class Solution: return result ``` +贪心法 ```python class Solution: def maxSubArray(self, nums): @@ -226,8 +227,18 @@ class Solution: if count <= 0: # 相当于重置最大子序起始位置，因为遇到负数一定是拉低总和 count = 0 return result - - +``` +动态规划 +```python +class Solution: + def maxSubArray(self, nums: List[int]) -> int: + dp = [0] * len(nums) + dp[0] = nums[0] + res = nums[0] + for i in range(1, len(nums)): + dp[i] = max(dp[i-1] + nums[i], nums[i]) + res = max(res, dp[i]) + return res ``` ### Go 贪心法 From 2841f59212a4f8399d53007eb01130172ce59814 Mon Sep 17 00:00:00 2001 From: suinming <0223314338aa@gmail.com> Date: Tue, 24 Sep 2024 14:41:38 +0800 Subject: [PATCH 4/5] =?UTF-8?q?feat:=20108.=20=E5=86=97=E4=BD=99=E8=BF=9E?= =?UTF-8?q?=E6=8E=A5=E6=96=B0=E5=A2=9Epython=E8=A7=A3=E6=B3=95?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- problems/kamacoder/0108.冗余连接.md | 39 +++++++++++++++++++++++++ 1 file changed, 39 insertions(+) diff --git a/problems/kamacoder/0108.冗余连接.md b/problems/kamacoder/0108.冗余连接.md index 2c133782..18a86ad6 100644 --- a/problems/kamacoder/0108.冗余连接.md +++ b/problems/kamacoder/0108.冗余连接.md @@ -178,6 +178,45 @@ int main() { ### Python +```python +father = list() + +def find(u): + if u == father[u]: + return u + else: + father[u] = find(father[u]) + return father[u] + +def is_same(u, v): + u = find(u) + v = find(v) + return u == v + +def join(u, v): + u = find(u) + v = find(v) + if u != v: + father[u] = v + +if __name__ == "__main__": + # 輸入 + n = int(input()) + for i in range(n + 1): + father.append(i) + # 尋找冗余邊 + result = None + for i in range(n): + s, t = map(int, input().split()) + if is_same(s, t): + result = str(s) + ' ' + str(t) + else: + join(s, t) + + # 輸出 + print(result) +``` + ### Go ### Rust From 5c67ef4acd04b228b2f24f32a89917d9abc478b0 Mon Sep 17 00:00:00 2001 From: suinming <0223314338aa@gmail.com> Date: Tue, 24 Sep 2024 16:13:28 +0800 Subject: [PATCH 5/5] =?UTF-8?q?feat:=20109.=20=E5=86=97=E4=BD=99=E8=BF=9E?= =?UTF-8?q?=E6=8E=A5II=E6=96=B0=E5=A2=9Epython=E8=A7=A3=E6=B3=95?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- problems/kamacoder/0109.冗余连接II.md | 86 +++++++++++++++++++++++ 1 file changed, 86 insertions(+) diff --git a/problems/kamacoder/0109.冗余连接II.md b/problems/kamacoder/0109.冗余连接II.md index bd707bf6..2bd4eac6 100644 --- a/problems/kamacoder/0109.冗余连接II.md +++ b/problems/kamacoder/0109.冗余连接II.md @@ -351,6 +351,92 @@ public class Main { ``` ### Python +```python +from collections import defaultdict + +father = list() + + +def find(u): + if u == father[u]: + return u + else: + father[u] = find(father[u]) + return father[u] + + +def is_same(u, v): + u = find(u) + v = find(v) + return u == v + + +def join(u, v): + u = find(u) + v = find(v) + if u != v: + father[u] = v + + +def is_tree_after_remove_edge(edges, edge, n): + # 初始化并查集 + global father + father = [i for i in range(n + 1)] + + for i in range(len(edges)): + if i == edge: + continue + s, t = edges[i] + if is_same(s, t): # 成環，即不是有向樹 + return False + else: # 將s,t放入集合中 + join(s, t) + return True + + +def get_remove_edge(edges): + # 初始化并查集 + global father + father = [i for i in range(n + 1)] + + for s, t in edges: + if is_same(s, t): + print(s, t) + return + else: + join(s, t) + + +if __name__ == "__main__": + # 輸入 + n = int(input()) + edges = list() + in_degree = defaultdict(int) + + for i in range(n): + s, t = map(int, input().split()) + in_degree[t] += 1 + edges.append([s, t]) + + # 尋找入度為2的邊，並紀錄其下標(index) + vec = list() + for i in range(n - 1, -1, -1): + if in_degree[edges[i][1]] == 2: + vec.append(i) + + # 輸出 + if len(vec) > 0: + # 情況一：刪除輸出順序靠後的邊 + if is_tree_after_remove_edge(edges, vec[0], n): + print(edges[vec[0]][0], edges[vec[0]][1]) + # 情況二：只能刪除特定的邊 + else: + print(edges[vec[1]][0], edges[vec[1]][1]) + else: + # 情況三： 原圖有環 + get_remove_edge(edges) +``` + ### Go ### Rust