Merge pull request neetcode-gh#902 from FahadulShadhin/c-solutions

Adding 217-Contains-Duplicate.c

c/217-Contains-Duplicate.c

@@ -0,0 +1,42 @@
+/*
+ Time: O(n)
+ Space: O(1)
+*/
+
+typedef struct {
+ int key;
+ UT_hash_handle hh; // Makes this structure hashable
+} hash_table;
+
+hash_table *hash = NULL, *elem, *tmp;
+
+bool containsDuplicate(int* nums, int numsSize){
+ if (numsSize == 1) {
+ return false;
+ }
+
+ bool flag = false;
+
+ for (int i=0; i<numsSize; i++) {
+ HASH_FIND_INT(hash, &nums[i], elem);
+
+ if(!elem) {
+ elem = malloc(sizeof(hash_table));
+ elem->key = nums[i];
+ HASH_ADD_INT(hash, key, elem);
+
+ flag = false;
+ }
+ else {
+ flag = true;
+ break;
+ }
+ }
+
+ // Free up the hash table 
+ HASH_ITER(hh, hash, elem, tmp) {
+ HASH_DEL(hash, elem); free(elem);
+ }
+
+ return flag;
+}