Group anagrams

Author: holman57

Group_Anagrams.c

@@ -0,0 +1,62 @@
+/*
+Given an array of strings strs, group the anagrams together. You can return the answer in any order.
+
+An Anagram is a word or phrase formed by rearranging the letters of a different word or phrase,
+typically using all the original letters exactly once.
+
+Example 1:
+
+Input: strs = ["eat","tea","tan","ate","nat","bat"]
+Output: [["bat"],["nat","tan"],["ate","eat","tea"]]
+Example 2:
+
+Input: strs = [""]
+Output: [[""]]
+Example 3:
+
+Input: strs = ["a"]
+Output: [["a"]]
+ * */
+#define KEYLEN 128
+
+typedef struct {
+    char key[KEYLEN];
+    int listSize;
+    char **list;
+    UT_hash_handle hh;
+} Map;
+
+int cmpFunc(const void *a, const void *b) { return *(char *) a - *(char *) b; }
+
+char ***groupAnagrams(char **strs, int strsSize, int **columnSizes, int *returnSize) {
+    Map *map = NULL, *elem = NULL, *tmp;
+    char strBuf[KEYLEN], ***result;
+    int mapIndx = 0;
+    if (strsSize <= 0) return NULL;
+    for (int i = 0; i < strsSize; i++) {
+        strncpy(strBuf, strs[i], KEYLEN);
+        qsort(strBuf, strlen(strs[i]), sizeof(char), cmpFunc);
+        HASH_FIND_STR(map, strBuf, elem);
+        if (!elem) {
+            elem = malloc(sizeof(Map));
+            strncpy(elem->key, strBuf, KEYLEN);
+            elem->listSize = 1;
+            elem->list = malloc(sizeof(char **));
+            elem->list[0] = strs[i];
+            HASH_ADD_STR(map, key, elem);
+        } else {
+            elem->listSize++;
+            elem->list = realloc(elem->list, elem->listSize * sizeof(char **));
+            elem->list[elem->listSize - 1] = strs[i];
+        }
+    }
+    *returnSize = HASH_COUNT(map);
+    result = malloc(*returnSize * sizeof(char **));
+    *columnSizes = malloc(*returnSize * sizeof(int));
+    HASH_ITER(hh, map, elem, tmp)
+    {
+        (*columnSizes)[mapIndx] = elem->listSize;
+        result[mapIndx++] = elem->list;
+    }
+    return result;
+}