diff --git "a/01-\346\225\260\347\273\204/day04/problem_solving_05.py" "b/01-\346\225\260\347\273\204/day04/problem_solving_05.py"
new file mode 100644
index 0000000000000000000000000000000000000000..715f0d9df65d6764b4b02c29ed9e06b113e471c9
--- /dev/null
+++ "b/01-\346\225\260\347\273\204/day04/problem_solving_05.py"
@@ -0,0 +1,50 @@
+"""
+过桥的时间
+"""
+import heapq
+from typing import List
+
+
+class Solution:
+    def findCrossingTime(self, n: int, k: int, time: List[List[int]]) -> int:
+        time.sort(key=lambda t: t[0] + t[2])  # 稳定排序
+        cur = 0
+        workL, waitL, waitR, workR = [], [[-i, 0] for i in range(k - 1, -1, -1)], [], []  # 下标越大效率越低
+        while n:
+            while workL and workL[0][0] <= cur:
+                p = heapq.heappop(workL)
+                p[0], p[1] = p[1], p[0]
+                heapq.heappush(waitL, p)  # 左边完成放箱
+            while workR and workR[0][0] <= cur:
+                p = heapq.heappop(workR)
+                p[0], p[1] = p[1], p[0]
+                heapq.heappush(waitR, p)  # 右边完成搬箱
+            if waitR:  # 右边过桥，注意加到 waitR 中的都是 <= cur 的（下同）
+                p = heapq.heappop(waitR)
+                cur += time[-p[0]][2]
+                p[1] = p[0]
+                p[0] = cur + time[-p[0]][3]
+                heapq.heappush(workL, p)  # 放箱
+            elif waitL:  # 左边过桥
+                p = heapq.heappop(waitL)
+                cur += time[-p[0]][0]
+                p[1] = p[0]
+                p[0] = cur + time[-p[0]][1]
+                heapq.heappush(workR, p)  # 搬箱
+                n -= 1
+            elif len(workL) == 0:
+                cur = workR[0][0]  # cur 过小，找个最小的放箱/搬箱完成时间来更新 cur
+            elif len(workR) == 0:
+                cur = workL[0][0]
+            else:
+                cur = min(workL[0][0], workR[0][0])
+        while workR:
+            t, i = heapq.heappop(workR)  # 右边完成搬箱
+            # 如果没有排队，直接过桥；否则由于无论谁先过桥，最终完成时间都一样，所以也可以直接计算
+            cur = max(t, cur) + time[-i][2]
+        return cur  # 最后一个过桥的时间
+
+
+if __name__ == '__main__':
+    result = Solution().findCrossingTime(1, 3, [[1, 1, 2, 1], [1, 1, 3, 1], [1, 1, 4, 1]])
+    print(result)