Sliding Window, Greedy Algorithm

Coding Test/122.py

@@ -0,0 +1,9 @@
+class Solution:
+    def maxProfit(self, prices: List[int]) -> int:
+        result = 0
+
+        for i in range(len(prices) - 1):
+            if prices[i+1] > prices[i]:
+                result += prices[i+1] - prices[i]
+
+        return result

Coding Test/134.py

@@ -0,0 +1,15 @@
+class Solution:
+    def canCompleteCircuit(self, gas: List[int], cost: List[int]) -> int:
+        if sum(gas) < sum(cost):
+            return -1
+
+
+        start, fuel = 0, 0
+        for i in range(len(gas)):
+            if gas[i] + fuel < cost[i]:
+                start = i + 1
+                fuel = 0
+            else:
+                fuel += gas[i] - cost[i]
+
+        return start

Coding Test/406.py

@@ -0,0 +1,20 @@
+import re
+import collections
+import itertools
+import heapq
+import bisect
+
+class Solution:
+    def reconstructQueue(self, people: List[List[int]]) -> List[List[int]]:
+        result = []
+        heap = []
+
+        for person in people:
+            heapq.heappush(heap, (-person[0], person[1]))
+
+
+        while heap:
+            person = heapq.heappop(heap)
+            result.insert(person[1], (-person[0], person[1]))
+
+        return result

Coding Test/424.py

@@ -0,0 +1,17 @@
+class Solution:
+    def characterReplacement(self, s: str, k: int) -> int:
+        left = right = 0
+
+        counts = collections.Counter()
+
+        for right in range(1, len(s) + 1):
+
+            counts[s[right-1]] += 1
+
+            max_char_n = counts.most_common(1)[0][1]
+
+            if right - left - max_char_n > k:
+                counts[s[left]] -= 1
+                left += 1
+
+        return right - left

Coding Test/455.py

@@ -0,0 +1,13 @@
+class Solution:
+    def findContentChildren(self, g: List[int], s: List[int]) -> int:
+        g.sort()
+        s.sort()
+
+        i = j = 0
+
+        while i < len(g) and j < len(s):
+            if g[i] <= s[j]:
+                i += 1
+            j += 1
+
+        return i

Coding Test/76.py

@@ -0,0 +1,30 @@
+import re
+import collections
+import itertools
+import heapq
+import bisect
+
+class Solution:
+    def minWindow(self, s: str, t: str) -> str:
+        need = collections.Counter(t)
+        missing = len(t)
+        left = start = end = 0
+
+        for right, char in enumerate(s, 1):
+            missing -= need[char] > 0
+            need[char] -= 1
+
+            if missing == 0:
+
+                while left < right and need[s[left]] < 0:
+                    need[s[left]] += 1
+                    left += 1
+
+                if not end or right - left <= end - start:
+                    start, end = left, right
+
+                # need[s[left]] += 1
+                # missing += 1
+                # left += 1
+
+        return s[start:end]