Created
August 17, 2020 05:48
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LRU cache cpp implementation
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#include <iostream> | |
#include <list> | |
#include <map> | |
class cache { | |
public: | |
cache(int s) : size(s) {}; | |
void put(int k) { | |
if (addressMap.find(k) != addressMap.end()) return; | |
contents.push_back(k); | |
addressMap[k] = --contents.end(); | |
if (contents.size() > size) { | |
addressMap.erase(contents.front()); | |
contents.pop_front(); | |
} | |
} | |
void get(int k) { | |
printf("val %d : ", k); | |
auto kIter = addressMap.find(k); | |
if (kIter != addressMap.end()) { | |
printf("Cache hit\n"); | |
contents.erase(addressMap[k]); | |
addressMap.erase(k); | |
} else { | |
printf("missed\n"); | |
} | |
put(k); | |
} | |
void printContents() { | |
printf("contents order: "); | |
for (const auto &c : contents) | |
printf("%d,", c); | |
printf("\ncontents map: "); | |
for (const auto &a : addressMap) | |
printf("%d,", a.first); | |
printf("\n"); | |
} | |
private: | |
std::list<int> contents; | |
int size; | |
std::map<int, std::list<int>::iterator> addressMap; | |
}; | |
int main() { | |
cache C(2); | |
C.put(1); | |
C.put(2); | |
C.put(3); | |
C.put(10); | |
C.printContents(); | |
C.get(3); C.printContents(); | |
C.get(30); C.printContents(); | |
C.get(20); C.printContents(); | |
C.put(3); | |
return 0; | |
} | |
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