7-51-两个有序链表序列的合并-编程题

解题代码

#include<stdio.h>
#include<stdlib.h>
typedef struct Node* List;
struct Node {
	int Data;
	List Next;
};
List Insert(List L, int temp);
void Merge(List head1, List head2, List head3);
void Print(List head);
int main()
{
	List head1 = (List)malloc(sizeof(struct Node));
	head1->Next = NULL;
	List head2 = (List)malloc(sizeof(struct Node));
	head2->Next = NULL;
	List L1 = head1, L2 = head2;
	int temp;
	while (1) {
		scanf("%d", &temp);
		if (temp == -1) break;
		else L1=Insert(L1, temp);
	}
	while (1) {
		scanf("%d", &temp);
		if (temp == -1) break;
		else L2=Insert(L2, temp);
	}
	List head3 = (List)malloc(sizeof(struct Node));
	head3->Next = NULL;
	Merge(head1, head2, head3);
	Print(head3);
	return 0;
}
List Insert(List L, int temp) {
	List add = (List)malloc(sizeof(struct Node));
	add->Data = temp;
	add->Next = NULL;
	L->Next = add;
	L = add;
	return add;
}
void Merge(List head1, List head2, List head3) {
	List t1 = head1->Next;
	List t2 = head2->Next;
	List t3 = head3;
	if (!t1) {
		if (!t2) {
			head3->Next = NULL;
		}
		else {
			head3->Next = t2;
		}
	}
	else if(!t2){
		head3->Next = t1;
	}
	else {
		while (t1 && t2) {
			if (t1->Data <= t2->Data) {
				t3 = Insert(t3, t1->Data);
				t1 = t1->Next;
			}
			else {
				t3 = Insert(t3, t2->Data);
				t2 = t2->Next;
			}
		}
		while (t1) {
			t3 = Insert(t3, t1->Data);
			t1 = t1->Next;
		}
		while (t2) {
			t3 = Insert(t3, t2->Data);
			t2 = t2->Next;
		}
	}
}
void Print(List head) {
	if (!head->Next) {
		printf("NULL");
	}
	else {
		List t = head->Next;
		int flag = 1;
		while (t) {
			if (flag) flag = 0;
			else printf(" ");
			printf("%d", t->Data);
			t = t->Next;
		}
	}
}

测试结果

问题整理

1.注意/不是NULL/的判断条件。