Merge pull request #2042 from CodingTestStudy2/변지협

[변지협] Day17

Author: github-actions[bot]

leetcode3/변지협/v3/385. Mini Parser.py

@@ -0,0 +1,108 @@
+'''
+겁나 이해하기 어려운 문제
+s = "[123,456,[788,799,833],[[]],10,[]]" 이테스트 케이스 통과를 못함.
+'''
+
+# """
+# This is the interface that allows for creating nested lists.
+# You should not implement it, or speculate about its implementation
+# """
+#class NestedInteger:
+#    def __init__(self, value=None):
+#        """
+#        If value is not specified, initializes an empty list.
+#        Otherwise initializes a single integer equal to value.
+#        """
+#
+#    def isInteger(self):
+#        """
+#        @return True if this NestedInteger holds a single integer, rather than a nested list.
+#        :rtype bool
+#        """
+#
+#    def add(self, elem):
+#        """
+#        Set this NestedInteger to hold a nested list and adds a nested integer elem to it.
+#        :rtype void
+#        """
+#
+#    def setInteger(self, value):
+#        """
+#        Set this NestedInteger to hold a single integer equal to value.
+#        :rtype void
+#        """
+#
+#    def getInteger(self):
+#        """
+#        @return the single integer that this NestedInteger holds, if it holds a single integer
+#        Return None if this NestedInteger holds a nested list
+#        :rtype int
+#        """
+#
+#    def getList(self):
+#        """
+#        @return the nested list that this NestedInteger holds, if it holds a nested list
+#        Return None if this NestedInteger holds a single integer
+#        :rtype List[NestedInteger]
+#        """
+
+class Solution:
+    def deserialize(self, s: str) -> NestedInteger:
+        if s[0] != '[':
+            return int(s)
+
+
+
+        s = [i for i in s]
+        str_tmp = ''
+        stack = []
+        lst_tmp = []
+        while s:
+            now = s.pop(0)
+            print('s,now:',s,now)
+            
+            if now == '[':
+                if lst_tmp:
+                    stack.append(lst_tmp)
+                lst_tmp = []
+                str_tmp = ''
+                s.pop()
+            elif now == ',':
+                lst_tmp.append(str_tmp)
+                str_tmp = ''
+            else:
+                str_tmp += now
+        
+        lst_tmp.append(str_tmp)
+        stack.append(lst_tmp)
+        
+        print(stack)
+
+        n = NestedInteger()
+        n.add(NestedInteger(789))
+
+        n1 = NestedInteger()
+        n1.add(NestedInteger(456))
+        n1.add(n)
+
+        n2 = NestedInteger()
+        n2.add(NestedInteger(123))
+        n2.add(NestedInteger(234))
+        n2.add(n1)
+
+        tmp = []
+        while stack:
+            # print(tmp)
+            s = stack.pop()
+            s = s[::-1]
+            n = NestedInteger()
+            while s:
+                t = s.pop()
+                n.add(NestedInteger(int(t)))
+            if tmp:
+                n.add(tmp[0])
+                tmp[0] = n
+            else:
+                tmp.append(n)
+
+        return tmp[0]

leetcode3/변지협/v3/463. Island Perimeter.py

@@ -0,0 +1,56 @@
+'''
+1. 아이디어:
+bfs로 섬을 탐색하면서, 섬의 가장자리를 만나면 perimeter를 1씩 증가시킨다.
+2. 시간복잡도:
+o(n)
+3. 알고리즘:
+bfs
+'''
+from collections import deque
+class Solution:
+    def islandPerimeter(self, grid: List[List[int]]) -> int:
+        x_len = len(grid[0])
+        y_len = len(grid)
+
+        directions = [(-1,0),(1,0),(0,1),(0,-1)]
+        visited = [[False] * x_len for _ in range(y_len)]
+        queue = deque()
+
+        for y in range(y_len):
+            breaker = False
+            for x in range(x_len):
+                if grid[y][x] == 1:
+                    queue.append((x,y))
+                    visited[y][x] = True
+                    breaker = True
+                    break
+            
+            if breaker:
+                break
+        
+        ans = 0
+        while queue:
+            x,y = queue.pop()
+            
+            if x == 0:
+                ans += 1
+            if x == x_len - 1:
+                ans += 1
+            if y == 0:
+                ans += 1
+            if y == y_len - 1:
+                ans += 1
+            
+            for dx,dy in directions:
+                if 0 <= dx + x < x_len and grid[y][dx+x] == 0:
+                    ans += 1
+                if 0 <= dy + y < y_len and grid[y+dy][x] == 0:
+                    ans += 1
+                
+                if 0 <= dx + x < x_len and 0 <= dy+ y < y_len and grid[y+dy][x+dx] == 1 and not visited[y+dy][x+dx]:
+                    queue.append((x+dx,y+dy))
+                    visited[y+dy][x+dx] = True
+
+        return ans
+            
+