added hm implementation

slides/exemples/hm/Makefile

+CC:=gcc
+CFLAGS:=-Wall -Wextra -pedantic -fsanitize=address -g
+LDFLAGS:=-fsanitize=address
+
+main: main.o hm.o
+
+main.o: hm.h
+hm.o: hm.h
+
+.PHONY: clean
+
+clean:
+	rm -f *.o main
+

slides/exemples/hm/hm.c

+#include "hm.h"
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+
+static int hash(char *key, int capacity) {
+    int h = 0;
+    for (int i = 0; i < (int)strlen(key); ++i) {
+        h = (h + key[i] * 43) % capacity;
+    }
+    return h;
+}
+
+// allocate memory of the table to capacity
+void hm_init(struct hm_t *hm, int capacity) {
+    hm->table = malloc(sizeof(*(hm->table)) * capacity);
+    hm->capacity = capacity;
+    hm->size = 0;
+    for (int i = 0; i < hm->capacity; ++i) {
+        hm->table[i].state = empty;
+    }
+}
+
+// insert the key - value pair: if key is already present
+// we erase the old value. if the table is full we return false
+bool hm_insert(struct hm_t *hm, char *key, char *value) {
+    int index = hash(key, hm->capacity);
+    int initial_index = index;
+    while (hm->table[index].state == occupied && strncmp(hm->table[index].key, key, MAX_LEN) != 0) {
+        index = (index + 1) % hm->capacity;
+        if (index == initial_index) {
+            return false;
+        }
+    }
+    hm->table[index].state = occupied;
+    strncpy(hm->table[index].key, key, MAX_LEN);
+    strncpy(hm->table[index].value, value, MAX_LEN);
+    hm->size += 1;
+
+    return true;
+}
+
+// changes the state of the table at the "key" position to deleted
+void hm_delete(struct hm_t *hm, char *key) {
+    int index = hash(key, hm->capacity);
+    int initial_index = index;
+    while (hm->table[index].state != empty) {
+        if (hm->table[index].state == occupied && strncmp(hm->table[index].key, key, MAX_LEN) == 0)
+        {
+            hm->table[index].state = deleted;
+            hm->size -= 1;
+        }
+        index = (index + 1) % hm->capacity;
+        if (index == initial_index) {
+            return;
+        }
+    }
+}
+
+// returns the value linked to the key if present
+// return NULL otherwise
+char *hm_get(struct hm_t hm, char *key) {
+    int index = hash(key, hm.capacity);
+    int initial_index = index;
+    while (hm.table[index].state != empty) {
+        if (hm.table[index].state == occupied && strncmp(hm.table[index].key, key, MAX_LEN) == 0) {
+            return hm.table[index].value;
+        }
+        index = (index + 1) % hm.capacity;
+        if (index == initial_index) {
+            return NULL;
+        }
+    }
+
+    return NULL;
+}
+
+// prints the state of the table
+void hm_print(struct hm_t hm) {
+    for (int i = 0; i < hm.capacity; ++i) {
+        if (hm.table[i].state == empty) {
+            printf("[%d]: empty\n", i);
+        } else if (hm.table[i].state == occupied) {
+            printf("[%d]: occupied, %s, %s\n", i, hm.table[i].key, hm.table[i].value);
+        } else {
+            printf("[%d]: deleted, %s, %s\n", i, hm.table[i].key, hm.table[i].value);
+        }
+    }
+}
+
+// frees ressources
+void hm_destroy(struct hm_t *hm) {
+    free(hm->table);
+    hm->table = NULL;
+    hm->size = -1;
+    hm->capacity = -1;
+}

slides/exemples/hm/hm.h

+#ifndef HM_H
+#define HM_H
+
+#include <stdbool.h>
+
+#define MAX_LEN 80
+
+typedef enum {occupied, empty, deleted} state_t;
+
+struct cell_t {
+    char key[MAX_LEN];
+    char value[MAX_LEN];
+    state_t state;
+};
+
+struct hm_t {
+    struct cell_t *table;
+    int size;
+    int capacity;
+};
+
+// allocate memory of the table to capacity
+void hm_init(struct hm_t *hm, int capacity);
+
+// insert the key - value pair: if key is already present
+// we erase the old value. if the table is full we return false
+bool hm_insert(struct hm_t *hm, char *key, char *value);
+
+// changes the state of the table at the "key" position to deleted
+void hm_delete(struct hm_t *hm, char *key);
+
+// returns the value linked to the key if present
+// return NULL otherwise
+char *hm_get(struct hm_t hm, char *key);
+
+// prints the state of the table
+void hm_print(struct hm_t hm);
+
+// frees ressources
+void hm_destroy(struct hm_t *hm);
+
+#endif // !HM_H

slides/exemples/hm/main.c

+#include <stdlib.h>
+#include <stdio.h>
+#include "hm.h"
+
+int main() {
+    struct hm_t hm;
+    hm_init(&hm, 10);
+    hm_print(hm);
+    hm_insert(&hm, "orestis", "123");
+    hm_insert(&hm, "paul", "234");
+    hm_insert(&hm, "delphine", "12lsk3");
+    hm_insert(&hm, "noria", "12as 3");
+    hm_insert(&hm, "andres", "123am");
+    /*hm_insert(&hm, "fabien", "236123");*/
+    hm_insert(&hm, "tewfik", "123skjs");
+    hm_insert(&hm, "florent", "12adsadcasd3");
+    hm_insert(&hm, "mickael", "123aaaaaaa");
+    hm_insert(&hm, "guido", "1asdljncaskjdnckajsd23");
+    hm_insert(&hm, "orestis", "1298392");
+    hm_print(hm);
+    printf("value is: %s\n", hm_get(hm, "orestis"));
+    printf("value is: %s\n", hm_get(hm, "guido"));
+    printf("value is: %s\n", hm_get(hm, "noria"));
+    printf("value is: %s\n", hm_get(hm, "bob"));
+
+    hm_delete(&hm, "fabien");
+    hm_delete(&hm, "paul");
+    hm_delete(&hm, "florent");
+    hm_delete(&hm, "orestis");
+    hm_delete(&hm, "paul");
+    hm_print(hm);
+    hm_insert(&hm, "paul", "aksjdnckajndcaksjdc");
+    hm_print(hm);
+
+    hm_destroy(&hm);
+    return EXIT_SUCCESS;
+}