LeetCode题解之Split Linked List in Parts

1、题目描述

2、题目分析

主要是理解题意，将每个子链表应该分得的节点个数计算清楚。利用除数和余数的方法进行计算。

3、代码

vector<ListNode*> splitListToParts(ListNode* root, int k) {
        vector<ListNode*> res(k, NULL);
        if (root == NULL) {
            return res;
        }
        
        int listlen = 0;
        ListNode *p = root;
        while (p != NULL) {
            listlen++;
            p = p->next;
        }
        
        int m = listlen / k;
        int n = listlen % k;
        
        if (m == 0) {
            p = root;
            for (int i = 0; i < n; i++) {
                res[i] = p;
                ListNode *pn = p->next;
                p->next = NULL;
                p = pn;
            }
        } else {
            p = root;
            int i;
            for(i = 0; i < k; i++) {
                ListNode *pn;
                res[i] = p;
                int step = (i < n)? m:m-1;
                while(step--) {
                    p = p->next;
                }
                pn = p->next;
                p->next = NULL;
                p = pn;
                if (p == NULL)
                    break;
                }
            }
        
        
        return res;
        
        
               
    }