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384#include <assert.h>
#include <rbtree.h>
#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
// new_rbtree should return rbtree struct with null root node
void test_init(void) {
rbtree *t = new_rbtree();
assert(t != NULL);
#ifdef SENTINEL
assert(t->nil != NULL);
assert(t->root == t->nil);
#else
assert(t->root == NULL);
#endif
delete_rbtree(t);
}
// root node should have proper values and pointers
void test_insert_single(const key_t key) {
rbtree *t = new_rbtree();
node_t *p = rbtree_insert(t, key);
assert(p != NULL);
assert(t->root == p);
assert(p->key == key);
// assert(p->color == RBTREE_BLACK); // color of root node should be black
#ifdef SENTINEL
assert(p->left == t->nil);
assert(p->right == t->nil);
assert(p->parent == t->nil);
#else
assert(p->left == NULL);
assert(p->right == NULL);
assert(p->parent == NULL);
#endif
delete_rbtree(t);
}
// find should return the node with the key or NULL if no such node exists
void test_find_single(const key_t key, const key_t wrong_key) {
rbtree *t = new_rbtree();
node_t *p = rbtree_insert(t, key);
node_t *q = rbtree_find(t, key);
assert(q != NULL);
assert(q->key == key);
assert(q == p);
q = rbtree_find(t, wrong_key);
assert(q == NULL);
delete_rbtree(t);
}
// erase should delete root node
void test_erase_root(const key_t key) {
rbtree *t = new_rbtree();
node_t *p = rbtree_insert(t, key);
assert(p != NULL);
assert(t->root == p);
assert(p->key == key);
rbtree_erase(t, p);
#ifdef SENTINEL
assert(t->root == t->nil);
#else
assert(t->root == NULL);
#endif
delete_rbtree(t);
}
static void insert_arr(rbtree *t, const key_t *arr, const size_t n) {
for (size_t i = 0; i < n; i++) {
rbtree_insert(t, arr[i]);
}
}
static int comp(const void *p1, const void *p2) {
const key_t *e1 = (const key_t *)p1;
const key_t *e2 = (const key_t *)p2;
if (*e1 < *e2) {
return -1;
} else if (*e1 > *e2) {
return 1;
} else {
return 0;
}
};
// min/max should return the min/max value of the tree
void test_minmax(key_t *arr, const size_t n) {
// null array is not allowed
assert(n > 0 && arr != NULL);
rbtree *t = new_rbtree();
assert(t != NULL);
insert_arr(t, arr, n);
assert(t->root != NULL);
#ifdef SENTINEL
assert(t->root != t->nil);
#endif
qsort((void *)arr, n, sizeof(key_t), comp);
node_t *p = rbtree_min(t);
assert(p != NULL);
assert(p->key == arr[0]);
node_t *q = rbtree_max(t);
assert(q != NULL);
assert(q->key == arr[n - 1]);
rbtree_erase(t, p);
p = rbtree_min(t);
assert(p != NULL);
assert(p->key == arr[1]);
if (n >= 2) {
rbtree_erase(t, q);
q = rbtree_max(t);
assert(q != NULL);
assert(q->key == arr[n - 2]);
}
delete_rbtree(t);
}
void test_to_array(rbtree *t, const key_t *arr, const size_t n) {
assert(t != NULL);
insert_arr(t, arr, n);
qsort((void *)arr, n, sizeof(key_t), comp);
key_t *res = calloc(n, sizeof(key_t));
rbtree_to_array(t, res, n);
for (int i = 0; i < n; i++) {
assert(arr[i] == res[i]);
}
free(res);
}
void test_multi_instance() {
rbtree *t1 = new_rbtree();
assert(t1 != NULL);
rbtree *t2 = new_rbtree();
assert(t2 != NULL);
key_t arr1[] = {10, 5, 8, 34, 67, 23, 156, 24, 2, 12, 24, 36, 990, 25};
const size_t n1 = sizeof(arr1) / sizeof(arr1[0]);
insert_arr(t1, arr1, n1);
qsort((void *)arr1, n1, sizeof(key_t), comp);
key_t arr2[] = {4, 8, 10, 5, 3};
const size_t n2 = sizeof(arr2) / sizeof(arr2[0]);
insert_arr(t2, arr2, n2);
qsort((void *)arr2, n2, sizeof(key_t), comp);
key_t *res1 = calloc(n1, sizeof(key_t));
rbtree_to_array(t1, res1, n1);
for (int i = 0; i < n1; i++) {
assert(arr1[i] == res1[i]);
}
key_t *res2 = calloc(n2, sizeof(key_t));
rbtree_to_array(t2, res2, n2);
for (int i = 0; i < n2; i++) {
assert(arr2[i] == res2[i]);
}
free(res2);
free(res1);
delete_rbtree(t2);
delete_rbtree(t1);
}
// Search tree constraint
// The values of left subtree should be less than or equal to the current node
// The values of right subtree should be greater than or equal to the current
// node
static bool search_traverse(const node_t *p, key_t *min, key_t *max,
node_t *nil) {
if (p == nil) {
return true;
}
*min = *max = p->key;
key_t l_min, l_max, r_min, r_max;
l_min = l_max = r_min = r_max = p->key;
const bool lr = search_traverse(p->left, &l_min, &l_max, nil);
if (!lr || l_max > p->key) {
return false;
}
const bool rr = search_traverse(p->right, &r_min, &r_max, nil);
if (!rr || r_min < p->key) {
return false;
}
*min = l_min;
*max = r_max;
return true;
}
void test_search_constraint(const rbtree *t) {
assert(t != NULL);
node_t *p = t->root;
key_t min, max;
#ifdef SENTINEL
node_t *nil = t->nil;
#else
node_t *nil = NULL;
#endif
assert(search_traverse(p, &min, &max, nil));
}
// Color constraint
// 1. Each node is either red or black. (by definition)
// 2. All NIL nodes are considered black.
// 3. A red node does not have a red child.
// 4. Every path from a given node to any of its descendant NIL nodes goes
// through the same number of black nodes.
bool touch_nil = false;
int max_black_depth = 0;
static void init_color_traverse(void) {
touch_nil = false;
max_black_depth = 0;
}
static bool color_traverse(const node_t *p, const color_t parent_color,
const int black_depth, node_t *nil) {
if (p == nil) {
if (!touch_nil) {
touch_nil = true;
max_black_depth = black_depth;
} else if (black_depth != max_black_depth) {
return false;
}
return true;
}
if (parent_color == RBTREE_RED && p->color == RBTREE_RED) {
return false;
}
int next_depth = ((p->color == RBTREE_BLACK) ? 1 : 0) + black_depth;
return color_traverse(p->left, p->color, next_depth, nil) &&
color_traverse(p->right, p->color, next_depth, nil);
}
void test_color_constraint(const rbtree *t) {
assert(t != NULL);
#ifdef SENTINEL
node_t *nil = t->nil;
#else
node_t *nil = NULL;
#endif
node_t *p = t->root;
assert(p == nil || p->color == RBTREE_BLACK);
init_color_traverse();
assert(color_traverse(p, RBTREE_BLACK, 0, nil));
}
// rbtree should keep search tree and color constraints
void test_rb_constraints(const key_t arr[], const size_t n) {
rbtree *t = new_rbtree();
assert(t != NULL);
insert_arr(t, arr, n);
assert(t->root != NULL);
test_color_constraint(t);
test_search_constraint(t);
delete_rbtree(t);
}
// rbtree should manage distinct values
void test_distinct_values() {
const key_t entries[] = {10, 5, 8, 34, 67, 23, 156, 24, 2, 12};
const size_t n = sizeof(entries) / sizeof(entries[0]);
test_rb_constraints(entries, n);
}
// rbtree should manage values with duplicate
void test_duplicate_values() {
const key_t entries[] = {10, 5, 5, 34, 6, 23, 12, 12, 6, 12};
const size_t n = sizeof(entries) / sizeof(entries[0]);
test_rb_constraints(entries, n);
}
void test_minmax_suite() {
key_t entries[] = {10, 5, 8, 34, 67, 23, 156, 24, 2, 12};
const size_t n = sizeof(entries) / sizeof(entries[0]);
test_minmax(entries, n);
}
void test_to_array_suite() {
rbtree *t = new_rbtree();
assert(t != NULL);
key_t entries[] = {10, 5, 8, 34, 67, 23, 156, 24, 2, 12, 24, 36, 990, 25};
const size_t n = sizeof(entries) / sizeof(entries[0]);
test_to_array(t, entries, n);
delete_rbtree(t);
}
void test_find_erase(rbtree *t, const key_t *arr, const size_t n) {
for (int i = 0; i < n; i++) {
node_t *p = rbtree_insert(t, arr[i]);
assert(p != NULL);
}
for (int i = 0; i < n; i++) {
node_t *p = rbtree_find(t, arr[i]);
// printf("arr[%d] = %d\n", i, arr[i]);
assert(p != NULL);
assert(p->key == arr[i]);
rbtree_erase(t, p);
}
for (int i = 0; i < n; i++) {
node_t *p = rbtree_find(t, arr[i]);
assert(p == NULL);
}
for (int i = 0; i < n; i++) {
node_t *p = rbtree_insert(t, arr[i]);
assert(p != NULL);
node_t *q = rbtree_find(t, arr[i]);
assert(q != NULL);
assert(q->key == arr[i]);
assert(p == q);
rbtree_erase(t, p);
q = rbtree_find(t, arr[i]);
assert(q == NULL);
}
}
void test_find_erase_fixed() {
const key_t arr[] = {10, 5, 8, 34, 67, 23, 156, 24, 2, 12, 24, 36, 990, 25};
const size_t n = sizeof(arr) / sizeof(arr[0]);
rbtree *t = new_rbtree();
assert(t != NULL);
test_find_erase(t, arr, n);
delete_rbtree(t);
}
void test_find_erase_rand(const size_t n, const unsigned int seed) {
srand(seed);
rbtree *t = new_rbtree();
key_t *arr = calloc(n, sizeof(key_t));
for (int i = 0; i < n; i++) {
arr[i] = rand();
}
test_find_erase(t, arr, n);
free(arr);
delete_rbtree(t);
}
int main(void) {
test_init();
test_insert_single(1024);
test_find_single(512, 1024);
test_erase_root(128);
test_find_erase_fixed();
test_minmax_suite();
test_to_array_suite();
test_distinct_values();
test_duplicate_values();
test_multi_instance();
test_find_erase_rand(10000, 17);
printf("Passed all tests!\n");
}