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parkj90/array.c

Last active June 9, 2019 03:13
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dynamic array
Raw
array.c
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "array.h"
array_t *array_new(void) {
array_t *array = malloc(sizeof(array_t));
if (array == NULL) {
return NULL;
}
array->size = 0;
array->data = NULL;
return array;
}
int array_get(array_t *array, unsigned int index, int *value) {
if (index >= array->size) {
return -1;
}
*value = array->data[index];
return 0;
}
int array_set(array_t *array, unsigned int index, int value) {
if (index >= array->size) {
return -1;
}
array->data[index] = value;
return 0;
}
int array_delete(array_t *array, unsigned int index) {
if (index >= array->size) {
return -1;
}
int last = array->data[array->size - 1];
int *temp = realloc(array->data, (array->size - 1) * sizeof(int));
if (array->size != 1 && temp == NULL) {
return -2;
}
array->data = temp;
array->size--;
if ((array->size - index ) > 1) {
memmove(array->data + index, array->data + index + 1, (array->size - index - 1) * sizeof(int));
}
if (index < array->size) {
array->data[array->size - 1] = last;
}
return 0;
}
int array_append(array_t *array, int value) {
int *temp = realloc(array->data, (array->size + 1) * sizeof(int));
if (temp == NULL) {
return -2;
}
array->data = temp;
array->data[array->size] = value;
array->size++;
return 0;
}
unsigned int array_length(array_t *array) {
return array->size;
}
void array_free(array_t *array) {
free(array->data);
free(array);
}
//dump to stdout for debugging
void array_dump(array_t *array) {
for (int i = 0; i < array->size; i++) {
printf("%d ", array->data[i]);
}
printf("\n");
}
Raw
array.h
//array.h
typedef struct {
unsigned int size;
int *data;
} array_t;
array_t *array_new(void);
int array_get(array_t *array, unsigned int index, int *value);
int array_set(array_t *array, unsigned int index, int value);
int array_delete(array_t *array, unsigned int index);
int array_append(array_t *array, int value);
unsigned int array_length(array_t *array);
void array_free(array_t *array);
//dump to stdout for debugging
void array_dump(array_t *array);
/* methods returning int should return:
0 on success
-1 on out of bounds
-2 on out of memory
*/
Raw
main.c
//main.c
#include <stdio.h>
#include <assert.h>
#include "array.h"
int main(void) {
array_t *arr = array_new();
if (!arr) {
perror("erorr allocating array");
return -1;
}
int value;
/* Test basic append and length */
assert(array_append(arr, 42) == 0);
assert(array_append(arr, -50) == 0);
assert(array_append(arr, 76) == 0);
assert(array_length(arr) == 3);
array_dump(arr); /* should print 42 -50 76 */
/* Test get */
assert(array_get(arr, 0, &value) == 0);
assert(value == 42);
assert(array_get(arr, 1, &value) == 0);
assert(value == -50);
assert(array_get(arr, 2, &value) == 0);
assert(value == 76);
/* Test out of bounds get */
assert(array_get(arr, 3, &value) == -1);
/* Test set */
assert(array_set(arr, 1, 25) == 0);
assert(array_get(arr, 1, &value) == 0);
assert(value == 25);
array_dump(arr); /* should print 42 25 76 */
/* Test removal of end element */
assert(array_delete(arr, 2) == 0);
assert(array_length(arr) == 2);
assert(array_get(arr, 0, &value) == 0);
assert(value == 42);
assert(array_get(arr, 1, &value) == 0);
assert(value == 25);
/* Test removal of middle element */
assert(array_append(arr, 10) == 0);
assert(array_length(arr) == 3);
assert(array_delete(arr, 1) == 0);
assert(array_length(arr) == 2);
assert(array_get(arr, 0, &value) == 0);
assert(value == 42);
assert(array_get(arr, 1, &value) == 0);
assert(value == 10);
/* Test removal of beginning element */
assert(array_append(arr, 23) == 0);
assert(array_length(arr) == 3);
assert(array_delete(arr, 0) == 0);
assert(array_length(arr) == 2);
assert(array_get(arr, 0, &value) == 0);
assert(value == 10);
assert(array_get(arr, 1, &value) == 0);
assert(value == 23);
array_free(arr);
return 0;
}
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