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Page Faults in LRU
Medium Accuracy: 38.92% Submissions: 21917 Points: 4

In operating systems that use paging for memory management, page replacement algorithm are needed to decide which page needs to be replaced when the new page comes in. Whenever a new page is referred and is not present in memory, the page fault occurs and Operating System replaces one of the existing pages with a newly needed page. Given a sequence of pages and memory capacity, your task is to find the number of page faults using Least Recently Used (LRU) Algorithm.

Input:
The first line of input contains an integer T denoting the number of test cases. Each test case contains n number of pages and next line contains space seaprated sequence of pages. The following line consist of the capacity of the memory.

Note: Pages are referred in the order left to right from the array (i.e index 0 page is referred first then index 1 and so on). Memory is empty at the start.

Output:
Output the number of page faults.

Constraints:
1<=T<=100
1<=n<=1000
4<=capacity<=100

Example:
Input:
2
9
5 0 1 3 2 4 1 0 5
4
8
3 1 0 2 5 4 1 2
4

Output:
8
7

Explanation:
Testcase 1:

memory allocated with 4 pages 5, 0, 1, 3: page fault = 4
page number 2 is required, replaces LRU 5: page fault = 4+1 = 5
page number 4 is required, replaces LRU 0: page fault = 5 + 1 = 6
page number 1 is required which is already present: page fault = 6 + 0 = 6
page number 0 is required which replaces LRU 1: page fault = 6 + 1 = 7
page number 5 is required which replaces LRU 3: page fault = 7 + 1  =8.

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Page Faults in LRU

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