Pavlov_Dmitry_cw

Pavlov_Dmitry_cw/src/HashTable.h

@@ -0,0 +1,89 @@
+#ifndef COURSEWORK_HASHTABLE_H
+#define COURSEWORK_HASHTABLE_H
+#include <iostream>
+#include <list>
+
+
+using namespace std;
+
+//Creating a hashtable class
+class HashTable{
+private:
+    list<int> *table;
+    int total_elements;
+
+    [[nodiscard]] int getHash(int key) const{
+        return key % total_elements;
+    }
+
+public:
+    //Contructor
+    explicit HashTable(int n){
+        total_elements = n;
+        table = new list<int>[total_elements];
+    }
+    //Insertion method
+    int insertElement(int key){
+        int operation_counter = 1;
+        unsigned hash = getHash(abs(key));
+        list<int>& valueList = table[hash];
+        for(auto& elem : valueList){
+            if (elem == key){
+                elem = key;
+                return operation_counter++;
+            }
+            operation_counter++;
+        }
+        int newElem = key;
+        table[hash].push_back(newElem);
+        return operation_counter;
+    }
+    //Removal method
+    void removeElement(int key){
+        int x = getHash(key);
+
+        list<int>::iterator i;
+        for (i = table[x].begin(); i != table[x].end(); i++) {
+            if (*i == key)
+                break;
+        }
+
+
+        if (i != table[x].end())
+            table[x].erase(i);
+        else{
+            cout << "[WARNING] Key not found!\n";
+        }
+
+    }
+    //Method to print all hash table
+    void printAll(){
+        for(int i = 0; i < total_elements; i++){
+            cout << "Index " << i << ": ";
+            for(int j : table[i]) {
+                cout << j << " => ";
+            }
+
+            cout << endl;
+        }
+    }
+    //Method to print list of values by key
+    void printSearch(int key){
+        for(int i = 0; i < total_elements; i++){
+            if (i == key){
+                for(int j : table[i]) {
+                    cout << j << " => ";
+                }
+            }
+
+        }
+    }
+    //Clear hash table values
+    void clear(){
+        delete [] table;
+        table = new list<int>[this->total_elements];
+    }
+};
+
+
+#endif //COURSEWORK_HASHTABLE_H

Pavlov_Dmitry_cw/src/main.cpp

@@ -0,0 +1,63 @@
+#include <iostream>
+#include "HashTable.h"
+#include <ctime>
+#include <random>
+
+using namespace std;
+
+
+int main() {
+    std::mt19937 rndGen(static_cast<unsigned>(time(nullptr))); // Generator Mersenne twister
+    int testCount = 512; // Start test data
+    for (int i = 0; i < 7; ++i) {
+        int operCounter = 0; // Operation counter
+        HashTable avrHT(testCount);
+
+        clock_t clocks;
+        float time = 0;
+        float avrTime;
+        avrHT.clear();
+        //
+        for (int j = 0; j < testCount; ++j) {
+            int value = static_cast<int>(rndGen()); // Generating a value
+            clocks = clock();
+            operCounter += avrHT.insertElement(value);
+
+            clocks = clock() - clocks;
+            time += static_cast<float>(clocks) / CLOCKS_PER_SEC;
+            }
+
+        if(i == 1){
+            avrHT.printAll();
+        }
+        avrTime = time / (float )testCount;
+        operCounter /= testCount;
+        std::cout << "Elements - " << testCount << " Average case insertion - " <<fixed<< avrTime << " sec " <<"Operation Counts - "<< operCounter << std::endl;
+        time = 0;
+
+
+
+        avrHT.clear();
+        long long int base = 1;
+        while (base <= testCount){
+            base <<= 1;
+        }
+        operCounter = 0;
+        for (int j = 0; j < testCount; ++j) {
+            long long int key = (j+1)*base;
+            clocks = clock();
+            operCounter += avrHT.insertElement(key);
+            clocks = clock() - clocks;
+            time += static_cast<float>(clocks) / CLOCKS_PER_SEC;
+        }
+
+
+
+        avrTime = time / (float )testCount;
+        operCounter /= testCount;
+        std::cout << "Elements - " << testCount << " Bad case insertion - " <<fixed<< avrTime << " sec" <<" Average operation counts - "<< operCounter << std::endl << std::endl;
+        testCount *= 2;
+
+    }
+    return 0;
+}