Write the code about Program for Least Recently used Algorithm in C++.1、 Create a page access sequence (page number range 0-18) using a random function. The sequence length is 54 and assume that the number of main memory frames allocated to the thread is 6, that is, M = 6. 2、 Implement the LRU algorithm for page replacement on the above access sequence. 3、 Output the page replacement sequence and the page fault rate.
时间: 2023-12-06 16:44:31 浏览: 35
```
#include <iostream>
#include <vector>
#include <algorithm>
using namespace std;
int main()
{
// Create page access sequence
vector<int> page_sequence;
srand(time(NULL));
for(int i=0;i<54;i++){
page_sequence.push_back(rand()%19);
}
// Implement LRU algorithm
int M = 6; // Number of main memory frames
vector<int> frames(M, -1); // Initialize frames with -1 (empty)
vector<int> used_bits(M, 0); // Initialize used_bits with 0
int page_faults = 0;
for(int i=0;i<54;i++){
int page = page_sequence[i];
int index = find(frames.begin(), frames.end(), page) - frames.begin();
if(index == M){ // Page fault
page_faults++;
int min_used_bit_index = min_element(used_bits.begin(), used_bits.end()) - used_bits.begin();
frames[min_used_bit_index] = page;
used_bits[min_used_bit_index] = 0;
}
else{ // Page hit
used_bits[index] = 0;
}
for(int j=0;j<M;j++){
if(j != index){
used_bits[j]++;
}
}
}
// Output results
cout << "Page Replacement Sequence: ";
for(int i=0;i<M;i++){
if(frames[i] != -1){
cout << frames[i] << " ";
}
}
cout << endl;
cout << "Page Fault Rate: " << (double)page_faults/54.0 << endl;
return 0;
}
```