hashing.cpp

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#define SIZE 10

struct KeyValue {
    char* key;
    int value;
};

struct KeyValue* hashTable[SIZE];

int hash(char* key) {
    int sum = 0;
    for (int i = 0; key[i] != '\0'; i++) {
        sum += key[i];
    }
    return sum % SIZE;
}

void insert(char* key, int value) {
    int index = hash(key);
    while (hashTable[index] != NULL) {
        index = (index + 1) % SIZE;
    }
    hashTable[index] = (struct KeyValue*)malloc(sizeof(struct KeyValue));
    hashTable[index]->key = strdup(key);
    hashTable[index]->value = value;
}

int search(char* key) {
    int index = hash(key);
    while (hashTable[index] != NULL) {
        if (strcmp(hashTable[index]->key, key) == 0) {
            return hashTable[index]->value;
        }
        index = (index + 1) % SIZE;
    }
    return -1; // Key not found
}

void display() {
    printf("Hash Table:\n");
    for (int i = 0; i < SIZE; i++) {
        if (hashTable[i] != NULL) {
            printf("[%d] -> %s:%d\n", i, hashTable[i]->key, hashTable[i]->value);
        } else {
            printf("[%d] -> NULL\n", i);
        }
    }
}

int main() {
    // Initialize hash table
    for (int i = 0; i < SIZE; i++) {
        hashTable[i] = NULL;
    }

    insert("apple", 10);
    insert("banana", 20);
    insert("orange", 30);
    insert("grape", 40);

    display();

    printf("\nSearch results:\n");
    printf("Value for 'apple': %d\n", search("apple"));
    printf("Value for 'banana': %d\n", search("banana"));
    printf("Value for 'orange': %d\n", search("orange"));
    printf("Value for 'grape': %d\n", search("grape"));
    printf("Value for 'cherry': %d\n", search("cherry"));

    return 0;
}