added Esercizi n. 1

Esercizi n. 1/main.c

+#include <stdio.h>
+#include <stdlib.h>
+
+typedef struct {
+    char first_name[20];
+    char last_name[25];
+    unsigned int age;
+} Person;
+
+void person_input(Person *person) {
+    puts("nome");
+    scanf("%s", person->first_name);
+    puts("cognome");
+    // FIXME: buffer overflow
+    scanf("%s", person->last_name);
+    puts("anni");
+    scanf("%u", &person->age);
+}
+
+void person_array_input(Person people[], size_t n) {
+    for (size_t i = 0; i < n; ++i) {
+        printf("persona %zu\n", i);
+        person_input(&people[i]);
+    }
+}
+
+void person_output(Person *person) {
+    printf(
+        "nome: %s, cognome: %s, anni: %u\n",
+        person->first_name,
+        person->last_name,
+        person->age
+    );
+}
+
+void person_array_idx_output(Person people[], size_t i) {
+    person_output(&people[i]);
+}
+
+void person_array_output(Person people[], size_t n) {
+    for (size_t i = 0; i < n; ++i) {
+        person_array_idx_output(people, i);
+    }
+}
+
+void split_adulthood(Person people[], size_t n, Person minors[], Person adults[]) {
+    minors = malloc(sizeof(*people) * n);
+    adults = malloc(sizeof(*people) * n);
+
+    size_t count_minors = 0;
+    size_t count_adults = 0;
+
+    for (size_t i = 0; i < n; ++i) {
+        Person *dst = people[i].age < 18
+          ? &minors[count_minors++]
+          : &adults[count_adults++];
+        *dst = people[i];
+    }
+
+    minors = realloc(minors, sizeof(*people) * count_minors);
+    adults = realloc(adults, sizeof(*people) * count_adults);
+}