1032 Sharing（链表）

比眉伴天荒 2024-04-08 11:34 74阅读 0赞

## 1032 Sharing（链表） ##

### 0、题目 ###

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.

![fig.jpg][]

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

where`Address` 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 `-1` instead.

#### 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: ####

67890

#### Sample Input 2: ####

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

#### Sample Output 2: ####

-1

### 1、大致题意 ###

求两个链表的首个共同结点的地址。如果没有，就输出-1

### 2、大致思路 ###

用结构体数组存储，node\[i\]表示地址为i的结点，key表示值，next为下一个结点的地址，flag表示第一条链表有没有该结点。遍历第一条链表，将访问过的结点的flag都标记为true，当遍历第二条结点的时候，如果遇到了true的结点就输出并结束程序，没有遇到就输出-1。

### 3、AC代码 ###

#include <cstdio>
    using namespace std;
    struct NODE {
        
        char key;
        int next;
        bool flag;
    }node[100000];
    int main() {
        
        int s1, s2, n, a, b;
        scanf("%d%d%d", &s1, &s2, &n);
        char data;
        for(int i = 0; i < n; i++) {
        
            scanf("%d %c %d", &a, &data, &b);
            node[a] = {
        data, b, false};
        }
        for(int i = s1; i != -1; i = node[i].next)
            node[i].flag = true;
        for(int i = s2; i != -1; i = node[i].next) {
        
            if(node[i].flag == true) {
        
                printf("%05d", i);
                return 0;
            }
        }
        printf("-1");
        return 0;
    }

[fig.jpg]: https://image.dandelioncloud.cn/pgy_files/images/2024/04/08/51b6c949eb694b46a75e89e8feff6765.jpeg