Create 1700.NumberofStudentsUnabletoEatLunch.py

Author: YuriSpiridonov

Easy/1700.NumberofStudentsUnabletoEatLunch.py

@@ -0,0 +1,85 @@
+'''
+    The school cafeteria offers circular and square sandwiches 
+    at lunch break, referred to by numbers 0 and 1 respectively. 
+    All students stand in a queue. Each student either prefers 
+    square or circular sandwiches.
+
+    The number of sandwiches in the cafeteria is equal to the 
+    number of students. The sandwiches are placed in a stack. 
+    At each step:
+        - If the student at the front of the queue prefers 
+          the sandwich on the top of the stack, they will 
+          take it and leave the queue.
+        - Otherwise, they will leave it and go to the queue's 
+          end.
+
+    This continues until none of the queue students want to 
+    take the top sandwich and are thus unable to eat.
+
+    You are given two integer arrays students and sandwiches 
+    where sandwiches[i] is the type of the i​​​​​​th sandwich in 
+    the stack (i = 0 is the top of the stack) and students[j] 
+    is the preference of the j​​​​​​th student in the initial queue 
+    (j = 0 is the front of the queue). Return the number of 
+    students that are unable to eat.
+
+    Example:
+    Input: students = [1,1,0,0], sandwiches = [0,1,0,1]
+    Output: 0 
+    Explanation:
+                - Front student leaves the top sandwich and 
+                  returns to the end of the line making 
+                  students = [1,0,0,1].
+                - Front student leaves the top sandwich and 
+                  returns to the end of the line making 
+                  students = [0,0,1,1].
+                - Front student takes the top sandwich and 
+                  leaves the line making students = [0,1,1] 
+                  and sandwiches = [1,0,1].
+                - Front student leaves the top sandwich and 
+                  eturns to the end of the line making 
+                  students = [1,1,0].
+                - Front student takes the top sandwich and 
+                  leaves the line making students = [1,0] 
+                  and sandwiches = [0,1].
+                - Front student leaves the top sandwich and 
+                  returns to the end of the line making 
+                  students = [0,1].
+                - Front student takes the top sandwich and 
+                  leaves the line making students = [1] and 
+                  sandwiches = [1].
+                - Front student takes the top sandwich and 
+                  leaves the line making students = [] and 
+                  sandwiches = [].
+                Hence all students are able to eat.
+
+    Example:
+    Input: students = [1,1,1,0,0,1], sandwiches = [1,0,0,0,1,1]
+    Output: 3
+
+    Constraints:
+        - 1 <= students.length, sandwiches.length <= 100
+        - students.length == sandwiches.length
+        - sandwiches[i] is 0 or 1.
+        - students[i] is 0 or 1.
+'''
+#Difficulty: Easy
+#55 / 55 test cases passed.
+#Runtime: 36 ms
+#Memory Usage: 14.4 MB
+
+#Runtime: 36 ms, faster than 84.36% of Python3 online submissions for Number of Students Unable to Eat Lunch.
+#Memory Usage: 14.4 MB, less than 23.56% of Python3 online submissions for Number of Students Unable to Eat Lunch.
+
+class Solution:
+    def countStudents(self, students: List[int], sandwiches: List[int]) -> int:
+        stuck_in_queue = 0
+        while stuck_in_queue < len(students):
+            student = students.pop(0)
+            if sandwiches[0] == student:
+                sandwiches.pop(0)
+                stuck_in_queue = 0
+            else:
+                students.append(student)
+                stuck_in_queue += 1
+        return stuck_in_queue