C语言 | Leetcode C语言题解之第429题N叉树的层序遍历
题目：
题解：
#define MAX_LEVE_SIZE 1000
#define MAX_NODE_SIZE 10000
int** levelOrder(struct Node* root, int* returnSize, int** returnColumnSizes) {
int ** ans = (int **)malloc(sizeof(int *) * MAX_LEVE_SIZE);
*returnColumnSizes = (int *)malloc(sizeof(int) * MAX_LEVE_SIZE);
if (!root) {
*returnSize = 0;
return ans;
}
struct Node ** queue = (struct Node **)malloc(sizeof(struct Node *) * MAX_NODE_SIZE);
int head = 0, tail = 0;
int level = 0;
queue[tail++] = root;
while (head != tail) {
int cnt = tail - head;
ans[level] = (int *)malloc(sizeof(int) * cnt);
for (int i = 0; i < cnt; ++i) {
struct Node * cur = queue[head++];
ans[level][i] = cur->val;
for (int j = 0; j < cur->numChildren; j++) {
queue[tail++] = cur->children[j];
}
}
(*returnColumnSizes)[level++] = cnt;
}
*returnSize = level;
free(queue);
return ans;
}