add 练习题.

.idea/.gitignore

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+# Default ignored files
+/shelf/
+/workspace.xml
+# Editor-based HTTP Client requests
+/httpRequests/
+# Datasource local storage ignored files
+/dataSources/
+/dataSources.local.xml

.idea/Algorithm.iml

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+<?xml version="1.0" encoding="UTF-8"?>
+<module type="PYTHON_MODULE" version="4">
+  <component name="NewModuleRootManager">
+    <content url="file://$MODULE_DIR$" />
+    <orderEntry type="inheritedJdk" />
+    <orderEntry type="sourceFolder" forTests="false" />
+  </component>
+</module>

.idea/inspectionProfiles/profiles_settings.xml

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+<component name="InspectionProjectProfileManager">
+  <settings>
+    <option name="USE_PROJECT_PROFILE" value="false" />
+    <version value="1.0" />
+  </settings>
+</component>

.idea/misc.xml

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+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="ProjectRootManager" version="2" project-jdk-name="Python 3.9" project-jdk-type="Python SDK" />
+</project>

.idea/modules.xml

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+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="ProjectModuleManager">
+    <modules>
+      <module fileurl="file://$PROJECT_DIR$/.idea/Algorithm.iml" filepath="$PROJECT_DIR$/.idea/Algorithm.iml" />
+    </modules>
+  </component>
+</project>

.idea/vcs.xml

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+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="VcsDirectoryMappings">
+    <mapping directory="$PROJECT_DIR$" vcs="Git" />
+  </component>
+</project>

lanqiao/main.py

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+import io
+import sys
+
+sys.stdin = io.StringIO('lanqiao')

lanqiao/test/2019省最短路-所有路.py

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+map_in = [
+    ['A', 'E', 1],
+    ['A', 'B', 2],
+    ['A', 'C', 1],
+    ['A', 'D', 1],
+    ['A', 'E', 1],
+    ['B', 'G', 1],
+    ['B', 'J', 2],
+    ['C', 'D', 3],
+    ['C', 'G', 3],
+    ['C', 'F', 3],
+    ['D', 'G', 2],
+    ['D', 'H', 1],
+    ['D', 'I', 2],
+    ['E', 'H', 1],
+    ['E', 'I', 3],
+    ['F', 'J', 1],
+    ['F', 'G', 1],
+    ['G', 'K', 2],
+    ['G', 'I', 3],
+    ['H', 'L', 2],
+    ['H', 'I', 1],
+    ['I', 'M', 3],
+    ['J', 'S', 2],
+    ['K', 'N', 1],
+    ['K', 'L', 3],
+    ['L', 'R', 1],
+    ['L', 'M', 1],
+    ['M', 'N', 2],
+    ['M', 'Q', 1],
+    ['M', 'S', 1],
+    ['N', 'P', 1],
+    ['Q', 'O', 1],
+    ['O', 'R', 3],
+    ['P', 'O', 1],
+    ['R', 'S', 1],
+]
+
+
+def dp(now_dis, next_node):
+    for src, dst, dis in map_in:
+        if src == next_node:
+            now_dis += dis
+            if dst == 'S':
+                ans.append(now_dis)
+            else:
+                dp(now_dis, dst)
+
+
+ans = []
+for src, dst, dis in map_in:
+    if src == 'A':
+        dp(dis, dst)
+
+print(min(ans))

lanqiao/test/2019省最短路.py

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+map_in = [
+    ['A', 'E', 1],
+    ['A', 'B', 2],
+    ['A', 'C', 1],
+    ['A', 'D', 1],
+    ['A', 'E', 1],
+    ['B', 'G', 1],
+    ['B', 'J', 2],
+    ['C', 'D', 3],
+    ['C', 'G', 3],
+    ['C', 'F', 3],
+    ['D', 'G', 2],
+    ['D', 'H', 1],
+    ['D', 'I', 2],
+    ['E', 'H', 1],
+    ['E', 'I', 3],
+    ['F', 'J', 1],
+    ['F', 'G', 1],
+    ['G', 'K', 2],
+    ['G', 'I', 3],
+    ['H', 'L', 2],
+    ['H', 'I', 1],
+    ['I', 'M', 3],
+    ['J', 'S', 2],
+    ['K', 'N', 1],
+    ['K', 'L', 3],
+    ['L', 'R', 1],
+    ['L', 'M', 1],
+    ['M', 'N', 2],
+    ['M', 'Q', 1],
+    ['M', 'S', 1],
+    ['N', 'P', 1],
+    ['Q', 'O', 1],
+    ['O', 'R', 3],
+    ['P', 'O', 1],
+    ['R', 'S', 1],
+]
+
+# 点的数量 数出来的
+n = 19
+# 初始化图 到自身到距离为0
+fig = [[float('inf')] * n for _ in range(n)]
+for i in range(n):
+    fig[i][i] = 0
+
+# 构建好路 每个节点之间的距离
+for src, dst, dis in map_in:
+    src, dst = ord(src) - ord('A'), ord(dst) - ord('A')
+    fig[src][dst] = fig[dst][src] = dis
+
+# 从起点到每个节点到距离 S为最后一个节点 因为是字母序排序的
+dis = [float('inf')] * n
+dis[0] = 0
+for i in range(n):
+    for j in range(n):
+        dis[j] = min(dis[j], dis[i] + fig[i][j])
+
+print(dis)
+print(dis[-1])

lanqiao/test/2020省单词分析.py

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+import io
+import sys
+
+sys.stdin = io.StringIO('lanqiao')
+
+s_in = input()
+counter = [0] * 26
+count_max = 0
+for ch in s_in:
+    idx = ord(ch) - ord('a')
+    counter[idx] += 1
+    count_max = max(count_max, counter[idx])
+
+for i in range(26):
+    if count_max == counter[i]:
+        print(chr(i + ord('a')))
+        print(count_max)
+        break

lanqiao/test/2020省回文日期.py

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+import io
+import sys
+
+sys.stdin = io.StringIO('20200202')
+
+import datetime
+
+s_in = input()
+year, month, day = int(s_in[:4]), int(s_in[4:6]), int(s_in[-2:])
+now = datetime.date(year, month, day)
+one_day = datetime.timedelta(days=1)
+
+reverse = True
+while True:
+    now += one_day
+    s = str(now).replace('-', '')
+    if reverse and s[::] == s[::-1]:
+        print(s)
+        reverse = False
+
+    # ABABBABA
+    if s[0] == s[2] == s[5] == s[7] and s[1] == s[3] == s[4] == s[6]:
+        print(s)
+        break