A1032 Sharing （25 分) ——PAT (Advanced Level) Practice

1032 Sharing （25 分)

To store English words, one method is to use linked lists and store a word letter by letter. To save some space, we may let the words share the same sublist if they share the same suffix. For example, loading and being are stored as showed in Figure 1.

Figure 1

You are supposed to find the starting position of the common suffix (e.g. the position of i in Figure 1).

Input Specification:

Each input file contains one test case. For each case, the first line contains two addresses of nodes and a positive N (≤105), where the two addresses are the addresses of the first nodes of the two words, and N is the total number of nodes. The address of a node is a 5-digit positive integer, and NULL is represented by −1.

Then N lines follow, each describes a node in the format:

Address Data Next

whereAddress is the position of the node, Data is the letter contained by this node which is an English letter chosen from { a-z, A-Z }, and Next is the position of the next node.

Output Specification:

For each case, simply output the 5-digit starting position of the common suffix. If the two words have no common suffix, output -1instead.

Sample Input 1:

11111 22222 9
67890 i 00002
00010 a 12345
00003 g -1
12345 D 67890
00002 n 00003
22222 B 23456
11111 L 00001
23456 e 67890
00001 o 00010

Sample Output 1:

Sample Input 2:

00001 00002 4
00001 a 10001
10001 s -1
00002 a 10002
10002 t -1

Sample Output 2:

-1

题意：给出两条链表的首地址以及若干节点的地址，数据，下地址，求两条链表公共部分的首个公共节点的地址。没有返回-1。

注意：题目给的地址范围较小，可以使用静态链表。

代码：

#include<stdio.h>
#include<stdlib.h>
#include<string.h>
using namespace std;
const int maxn=100010;

struct NODE
{
	char data;
	int  next;
	bool flag;
}node[maxn];

int main()
{
	for(int i=0;i<maxn;i++){
		node[i].flag=false;
	}
	int s1,s2,n;
	scanf("%d%d%d",&s1,&s2,&n);
	int address,next;
	char data;
	for(int i=0;i<n;i++){
		scanf("%d %c %d",&address,&data,&next);
		node[address].data = data;
		node[address].next = next; 
	}
	int p;
	for(p=s1;p!=-1;p=node[p].next){
		node[p].flag=true;//遍历串s1，并把每个标志记为1. 
	}
	for(p=s2;p!=-1;p=node[p].next){
		if(node[p].flag==true) break;
	}
	if(p!=-1){
		printf("%05d\n",p);
	} else{
		printf("-1\n");
	}
	return 0;
}