45 lines
1.3 KiB
Python
45 lines
1.3 KiB
Python
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class Optimal:
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def __init__(self, capacity):
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self.capacity = capacity
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self.cache = []
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def refer(self, page, future):
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if page not in self.cache:
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if len(self.cache) < self.capacity:
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self.cache.append(page)
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else:
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farthest_page = self.find_farthest_page(future)
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index = self.cache.index(farthest_page)
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self.cache[index] = page
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def find_farthest_page(self, future):
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farthest = -1
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farthest_page = None
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for page in self.cache:
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if page not in future:
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return page
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try:
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index = future.index(page)
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if index > farthest:
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farthest = index
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farthest_page = page
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except ValueError:
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continue
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return farthest_page
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def display(self):
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print("Current Pages in Memory (Optimal):", self.cache)
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# Simulate Optimal Page Replacement
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def optimal_simulation(pages, capacity):
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optimal = Optimal(capacity)
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for i in range(len(pages)):
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optimal.refer(pages[i], pages[i + 1:])
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optimal.display()
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# Example Pages and Capacity
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pages = [7, 0, 1, 2, 0, 3, 0, 4]
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capacity = 3
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print("\nOptimal Page Replacement Simulation:")
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optimal_simulation(pages, capacity)
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