题目描述
输入两个单调递增的链表，输出两个链表合成后的链表，当然我们需要合成后的链表满足单调不减规则。
1 /* 2 struct ListNode { 3 int val; 4 struct ListNode *next; 5 ListNode(int x) : 6 val(x), next(NULL) { 7 } 8 };*/ 9 class Solution { 10 public: 11 ListNode* Merge(ListNode* pHead1, ListNode* pHead2) 12 { 13 if (pHead1==NULL&&pHead2==NULL) return NULL; 14 15 ListNode* node; 16 ListNode* Node; 17 18 if (pHead1!=NULL&&pHead2!=NULL){ 19 if(pHead1->val < pHead2->val){ 20 node=pHead1; 21 Node=node; 22 pHead1=pHead1->next; 23 } 24 else{ 25 node=pHead2; 26 Node=node; 27 pHead2=pHead2->next; 28 } 29 } 30 else if (pHead1==NULL) return pHead2; 31 else if (pHead2==NULL) return pHead1; 32 while (pHead1!=NULL && pHead2!=NULL){ 33 if (pHead1->val < pHead2->val){ 34 node->next=pHead1; 35 node=node->next; 36 pHead1=pHead1->next; 37 } 38 else{ 39 node->next=pHead2; 40 node=node->next; 41 pHead2=pHead2->next; 42 } 43 } 44 if (pHead1!=NULL){ 45 node->next=pHead1; 46 } 47 else{ 48 node->next=pHead2; 49 } 50 return Node; 51 } 52 };