【CoderForces 501B】Misha and Changing Handles vector && pair
来源:互联网 发布:手机word文档软件 编辑:程序博客网 时间:2024/04/29 16:08
Description
Misha hacked the Codeforces site. Then he decided to let all the users change their handles. A user can now change his handle any number of times. But each new handle must not be equal to any handle that is already used or that was used at some point.
Misha has a list of handle change requests. After completing the requests he wants to understand the relation between the original and the new handles of the users. Help him to do that.
Input
The first line contains integer q (1 ≤ q ≤ 1000), the number of handle change requests.
Next q lines contain the descriptions of the requests, one per line.
Each query consists of two non-empty strings old and new, separated by a space. The strings consist of lowercase and uppercase Latin letters and digits. Strings old and new are distinct. The lengths of the strings do not exceed 20.
The requests are given chronologically. In other words, by the moment of a query there is a single person with handle old, and handlenew is not used and has not been used by anyone.
Output
In the first line output the integer n — the number of users that changed their handles at least once.
In the next n lines print the mapping between the old and the new handles of the users. Each of them must contain two strings, old andnew, separated by a space, meaning that before the user had handle old, and after all the requests are completed, his handle is new. You may output lines in any order.
Each user who changes the handle must occur exactly once in this description.
Sample Input
5Misha ILoveCodeforcesVasya PetrovPetrov VasyaPetrov123ILoveCodeforces MikeMirzayanovPetya Ivanov
3Petya IvanovMisha MikeMirzayanovVasya VasyaPetrov123
代码:#include<stdio.h>#include<algorithm>using namespace std; #include<string.h>#include<iostream>#include<vector>#include<string>#define f first #define s second int main(){int q;vector< pair<string,string> >d;string a,b;scanf("%d",&q);while(q--){cin>>a>>b; //必须用c++的输入输出; bool flag=false;//每次循环都置0; for(int i=0;i<d.size();i++){if(d[i].s==a){d[i].s=b;flag=true;}}if(!flag)//如果不可以改名,就把它们形成一组; {d.push_back(make_pair(a,b));}}printf("%d\n",d.size());for(int i=0;i<d.size();i++){cout<<d[i].f<<" "<<d[i].s<<endl;} return 0;}
- 【CoderForces 501B】Misha and Changing Handles vector && pair
- 【CodeForces】501B - Misha and Changing Handles(STL - string & vector & pair)
- CodeForces - 501B Misha and Changing Handles
- Codeforces 501 B - Misha and Changing Handles
- CF 501B Misha and Changing Handles
- CodeForces 501B Misha and Changing Handles
- codeforces 501B Misha and Changing Handles
- CodeForces 501B Misha and Changing Handles
- B - Misha and Changing Handles
- B. Misha and Changing Handles
- codeforces 501B B. Misha and Changing Handles
- Codeforces 501B - Misha and Changing Handles (STL)
- Codeforce exercise - 501B Misha and Changing Handles
- CodeForces 501B——Misha and Changing Handles
- CodeForces 501B Misha and Changing Handles(STL map)
- codeforces 501B Misha and Changing Handles(字符更换)
- CodeForces - 501B Misha and Changing Handles (map双向)
- I - Misha and Changing Handles CodeForces - 501B
- Unity3D NGUI 给2D不规则图形加碰撞盒
- 平常学习与实际应用场景
- Minimum Path Sum
- DRAM的动态刷新问题总结
- codeforces 711 A. Bus to Udayland
- 【CoderForces 501B】Misha and Changing Handles vector && pair
- 从数据库提取数据利用jpgraph画统计图柱形图
- Java8中的类型注解浅析
- 【C语言】二分查找一个数组中是否存在一个数字
- CSS清除浮动的方法
- 单链表的逆序存储
- 如何不用 List.clear() 方法 就清空 list 中的 所有元素(中兴面试)
- 阿里云CentOS7挂载SSD云盘的方法
- 玩LOL时出现错误:问题事件名称:APPCRASH 应用程序名:League of Legends.exe