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1995eaton/array.c

Last active November 18, 2015 13:09
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Dynamic arrays in C
Raw
array.c
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#define ARRAY_STRING
#if defined ARRAY_STRING
#define ARRAY_PRINT "s"
typedef char* array_t;
#else
#define ARRAY_PRINT "d"
typedef int array_t;
#endif
typedef struct Array {
array_t *data;
size_t capacity;
size_t length;
} Array;
Array create_array() {
Array arr;
arr.capacity = 8;
arr.length = 0;
arr.data = (array_t*) malloc(sizeof(array_t) * arr.capacity);
return arr;
}
void array_resize(Array *arr, size_t size) {
arr->data = realloc(arr->data, sizeof(array_t) * size);
arr->capacity = size;
}
void array_push(Array *arr, array_t item) {
arr->data[arr->length++] = item;
if (arr->length >= arr->capacity) {
array_resize(arr, arr->capacity * 2);
}
}
const array_t array_pop(Array *arr) {
if (arr->length > 0) {
return arr->data[--(arr->length)];
}
#if defined ARRAY_STRING
return NULL;
#else
return -1;
#endif
}
const array_t array_popn(Array *arr, int index) {
if (index < 0 || index >= arr->length) {
#if defined ARRAY_STRING
return NULL;
#else
return -1;
#endif
}
array_t item = arr->data[index];
arr->length--;
memmove(arr->data + index, arr->data + index + 1,
sizeof(array_t) * (arr->length - index));
return item;
}
const array_t array_get(Array *arr, int index) {
return arr->data[index];
}
void array_reverse(Array *arr) {
array_t *start = arr->data;
array_t *end = arr->data + arr->length - 1;
while (start < end) {
array_t temp = *start;
*start++ = *end;
*end-- = temp;
}
}
int array_indexof(Array *arr, array_t item) {
for (size_t i = 0; i < arr->length; i++) {
if (memcmp(&arr->data[i], &item, sizeof(array_t)) == 0) {
return i;
}
}
return -1;
}
void print_array(Array *arr) {
if (arr->length == 0) {
printf("[]\n");
return;
}
printf("[\n");
for (size_t i = 0; i < arr->length - 1; i++) {
printf(" %" ARRAY_PRINT ",\n", arr->data[i]);
}
printf(" %" ARRAY_PRINT "\n]\n", arr->data[arr->length - 1]);
}
void clear_array(Array *arr) {
#ifdef ARRAY_STRING
for (size_t i = 0; i < arr->length; i++) {
free(arr->data[i]);
}
#endif
free(arr->data);
arr->data = calloc(8, sizeof(array_t));
arr->capacity = 8;
arr->length = 0;
}
#include <sys/time.h>
char *random_string(int N) {
char *result = calloc(N, sizeof(char));
for (int i = 0; i < N; i++) {
result[i] = (int) (rand() % 93) + 33;
}
return result;
}
int main(void) {
struct timeval tv;
gettimeofday(&tv, NULL);
srand(tv.tv_usec * tv.tv_sec);
Array arr = create_array();
for (int i = 0; i < 100; i++) {
array_push(&arr, random_string(80));
}
print_array(&arr);
clear_array(&arr);
return 0;
}
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