Implement array in c

Author: RichardWeiYang

c-cpp/05_array/array.c

@@ -0,0 +1,95 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+struct array {
+int size;
+int used;
+int *arr;
+};
+
+void dump(struct array *array)
+{
+int idx;
+
+for (idx = 0; idx < array->used; idx++)
+printf("[%02d]: %08d\n", idx, array->arr[idx]);
+}
+
+void alloc(struct array *array)
+{
+array->arr = (int *)malloc(array->size * sizeof(int));
+}
+
+int insert(struct array *array, int elem)
+{
+int idx;
+if (array->used >= array->size)
+return -1;
+
+for (idx = 0; idx < array->used; idx++) {
+if (array->arr[idx] > elem)
+break;
+}
+
+if (idx < array->used)
+memmove(&array->arr[array->used], &array->arr[idx],
+(array->used - idx) * sizeof(int));
+
+array->arr[idx] = elem;
+array->used++;
+return idx;
+}
+
+int delete(struct array *array, int idx)
+{
+if (idx < 0 || idx >= array->used)
+return -1;
+
+memmove(&array->arr[idx], &array->arr[idx+1],
+(array->used - idx) * sizeof(int));
+array->used--;
+return 0;
+}
+
+int search(struct array *array, int elem)
+{
+int idx;
+
+for (idx = 0; idx < array->used; idx++) {
+if (array->arr[idx] == elem)
+return idx;
+if (array->arr[idx] > elem)
+return -1;
+}
+
+return -1;
+}
+
+int main()
+{
+int idx;
+struct array ten_int = {10, 0, NULL};
+
+alloc(&ten_int);
+if (!ten_int.arr)
+return -1;
+insert(&ten_int, 1);
+insert(&ten_int, 3);
+insert(&ten_int, 2);
+printf("=== insert 1, 3, 2\n");
+dump(&ten_int);
+
+idx = search(&ten_int, 2);
+printf("2 is at position %d\n", idx);
+idx = search(&ten_int, 9);
+printf("9 is at position %d\n", idx);
+
+printf("=== delete [6] element \n");
+delete(&ten_int, 6);
+dump(&ten_int);
+printf("=== delete [0] element \n");
+delete(&ten_int, 0);
+dump(&ten_int);
+return 0;
+}