해시 테이블은 키-값 쌍을 저장하는 데 사용되는 데이터 구조입니다. 해시 함수는 해시 테이블에서 요소를 삽입하거나 검색할 배열의 인덱스를 계산하는 데 사용됩니다.
해시 테이블을 구현하는 C++ 프로그램입니다.
알고리즘
Begin Initialize the table size T_S to some integer value. Create a structure hashTableEntry to declare key k and value v. Create a class hashMapTable: Create a constructor hashMapTable to create the table. Create a hashFunc() function which return key mod T_S. Create a function Insert() to insert element at a key. Create a function SearchKey() to search element at a key. Create a function Remove() to remove element at a key. Call a destructor hashMapTable to destroy the objects created by the constructor. In main, perform switch operation and enter input as per choice. To insert key and values, call insert(). To search element, call SearchKey(). To remove element, call Remove(). End.
예시 코드
#include<iostream>
#include<cstdlib>
#include<string>
#include<cstdio>
using namespace std;
const int T_S = 200;
class HashTableEntry {
public:
int k;
int v;
HashTableEntry(int k, int v) {
this->k= k;
this->v = v;
}
};
class HashMapTable {
private:
HashTableEntry **t;
public:
HashMapTable() {
t = new HashTableEntry * [T_S];
for (int i = 0; i< T_S; i++) {
t[i] = NULL;
}
}
int HashFunc(int k) {
return k % T_S;
}
void Insert(int k, int v) {
int h = HashFunc(k);
while (t[h] != NULL && t[h]->k != k) {
h = HashFunc(h + 1);
}
if (t[h] != NULL)
delete t[h];
t[h] = new HashTableEntry(k, v);
}
int SearchKey(int k) {
int h = HashFunc(k);
while (t[h] != NULL && t[h]->k != k) {
h = HashFunc(h + 1);
}
if (t[h] == NULL)
return -1;
else
return t[h]->v;
}
void Remove(int k) {
int h = HashFunc(k);
while (t[h] != NULL) {
if (t[h]->k == k)
break;
h = HashFunc(h + 1);
}
if (t[h] == NULL) {
cout<<"No Element found at key "<<k<<endl;
return;
} else {
delete t[h];
}
cout<<"Element Deleted"<<endl;
}
~HashMapTable() {
for (int i = 0; i < T_S; i++) {
if (t[i] != NULL)
delete t[i];
delete[] t;
}
}
};
int main() {
HashMapTable hash;
int k, v;
int c;
while (1) {
cout<<"1.Insert element into the table"<<endl;
cout<<"2.Search element from the key"<<endl;
cout<<"3.Delete element at a key"<<endl;
cout<<"4.Exit"<<endl;
cout<<"Enter your choice: ";
cin>>c;
switch(c) {
case 1:
cout<<"Enter element to be inserted: ";
cin>>v;
cout<<"Enter key at which element to be inserted: ";
cin>>k;
hash.Insert(k, v);
break;
case 2:
cout<<"Enter key of the element to be searched: ";
cin>>k;
if (hash.SearchKey(k) == -1) {
cout<<"No element found at key "<<k<<endl;
continue;
} else {
cout<<"Element at key "<<k<<" : ";
cout<<hash.SearchKey(k)<<endl;
}
break;
case 3:
cout<<"Enter key of the element to be deleted: ";
cin>>k;
hash.Remove(k);
break;
case 4:
exit(1);
default:
cout<<"\nEnter correct option\n";
}
}
return 0;
} 출력
1.Insert element into the table 2.Search element from the key 3.Delete element at a key 4.Exit Enter your choice: 1 Enter element to be inserted: 1 Enter key at which element to be inserted: 1 1.Insert element into the table 2.Search element from the key 3.Delete element at a key 4.Exit Enter your choice: 1 Enter element to be inserted: 2 Enter key at which element to be inserted: 2 1.Insert element into the table 2.Search element from the key 3.Delete element at a key 4.Exit Enter your choice: 1 Enter element to be inserted: 4 Enter key at which element to be inserted: 5 1.Insert element into the table 2.Search element from the key 3.Delete element at a key 4.Exit Enter your choice: 1 Enter element to be inserted: 7 Enter key at which element to be inserted: 6 1.Insert element into the table 2.Search element from the key 3.Delete element at a key 4.Exit Enter your choice: 2 Enter key of the element to be searched: 7 No element found at key 7 1.Insert element into the table 2.Search element from the key 3.Delete element at a key 4.Exit Enter your choice: 2 Enter key of the element to be searched: 6 Element at key 6 : 7 1.Insert element into the table 2.Search element from the key 3.Delete element at a key 4.Exit Enter your choice: 3 Enter key of the element to be deleted: 1 Element Deleted 1.Insert element into the table 2.Search element from the key 3.Delete element at a key 4.Exit Enter your choice: 4