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. 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). Part 1: Modify the code given and make it more efficient. You can try to implement your own stack or your own Queue. Or you can use the sandwiches array as a stack without making a separate Stack class. Same with the students array.  Part 2: After modifying the code, explain how it works, and why it is more efficient than the solution that you started with. (Or, if it turns out that the change you made is not more efficient, try to explain why that might be).

Database System Concepts
7th Edition
ISBN:9780078022159
Author:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan
Publisher:Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan
Chapter1: Introduction
Section: Chapter Questions
Problem 1PE
icon
Related questions
Question

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. 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).

  • Part 1: Modify the code given and make it more efficient. You can try to implement your own stack or your own Queue. Or you can use the sandwiches array as a stack without making a separate Stack class. Same with the students array. 
  • Part 2: After modifying the code, explain how it works, and why it is more efficient than the solution that you started with. (Or, if it turns out that the change you made is not more efficient, try to explain why that might be).
class Solution {
public int countStudents (int[] students, int[] sandwiches) {
Stack<Integer> sammies = new Stack<Integer>();
for(int i = sandwiches.length - 1; i >= 0; i--) {
sammies.push(sandwiches [i]);
}
}
}
Queue<Integer> hungryStudents = new Linked List<Integer>();
for(int j = 0; j < students.length; j++) {
hungryStudents.add(students [j]);
}
boolean isHope = true;
while (!sammies.isEmpty() && isHope) {
int numHungryStudents = hungryStudents.size();
for (int s = 0; s < numHungryStudents; s++) {
int student = hungryStudents.remove();
if(student == sammies.peek()) {
sammies.pop();
}
else {
}
}
return
hungryStudents.add(student);
}
if (numHungryStudents
isHope = false;
==
hungryStudents.size();
hungryStudents.size())
Transcribed Image Text:class Solution { public int countStudents (int[] students, int[] sandwiches) { Stack<Integer> sammies = new Stack<Integer>(); for(int i = sandwiches.length - 1; i >= 0; i--) { sammies.push(sandwiches [i]); } } } Queue<Integer> hungryStudents = new Linked List<Integer>(); for(int j = 0; j < students.length; j++) { hungryStudents.add(students [j]); } boolean isHope = true; while (!sammies.isEmpty() && isHope) { int numHungryStudents = hungryStudents.size(); for (int s = 0; s < numHungryStudents; s++) { int student = hungryStudents.remove(); if(student == sammies.peek()) { sammies.pop(); } else { } } return hungryStudents.add(student); } if (numHungryStudents isHope = false; == hungryStudents.size(); hungryStudents.size())
Example 1:
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 returns 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 2:
Input: students = [1,1,1,0,0,1], sandwiches = [1,0,0,0,1,1]
Output: 3
Transcribed Image Text:Example 1: 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 returns 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 2: Input: students = [1,1,1,0,0,1], sandwiches = [1,0,0,0,1,1] Output: 3
Expert Solution
trending now

Trending now

This is a popular solution!

steps

Step by step

Solved in 5 steps with 2 images

Blurred answer
Knowledge Booster
Stack
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, computer-science and related others by exploring similar questions and additional content below.
Similar questions
Recommended textbooks for you
Database System Concepts
Database System Concepts
Computer Science
ISBN:
9780078022159
Author:
Abraham Silberschatz Professor, Henry F. Korth, S. Sudarshan
Publisher:
McGraw-Hill Education
Starting Out with Python (4th Edition)
Starting Out with Python (4th Edition)
Computer Science
ISBN:
9780134444321
Author:
Tony Gaddis
Publisher:
PEARSON
Digital Fundamentals (11th Edition)
Digital Fundamentals (11th Edition)
Computer Science
ISBN:
9780132737968
Author:
Thomas L. Floyd
Publisher:
PEARSON
C How to Program (8th Edition)
C How to Program (8th Edition)
Computer Science
ISBN:
9780133976892
Author:
Paul J. Deitel, Harvey Deitel
Publisher:
PEARSON
Database Systems: Design, Implementation, & Manag…
Database Systems: Design, Implementation, & Manag…
Computer Science
ISBN:
9781337627900
Author:
Carlos Coronel, Steven Morris
Publisher:
Cengage Learning
Programmable Logic Controllers
Programmable Logic Controllers
Computer Science
ISBN:
9780073373843
Author:
Frank D. Petruzella
Publisher:
McGraw-Hill Education