1077. Kuchiguse (20)

The Japanese language is notorious for its sentence ending particles. Personal preference of such particles can be considered as a reflection of the speaker's personality. Such a preference is called "Kuchiguse" and is often exaggerated artistically in Anime and Manga. For example, the artificial sentence ending particle "nyan~" is often used as a stereotype for characters with a cat-like personality:

Itai nyan~ (It hurts, nyan~)
Ninjin wa iyada nyan~ (I hate carrots, nyan~)
Now given a few lines spoken by the same character, can you find her Kuchiguse?

Input Specification:

Each input file contains one test case. For each case, the first line is an integer N (2<=N<=100). Following are N file lines of 0~256 (inclusive) characters in length, each representing a character's spoken line. The spoken lines are case sensitive.

Output Specification:

For each test case, print in one line the kuchiguse of the character, i.e., the longest common suffix of all N lines. If there is no such suffix, write "nai".

Sample Input 1:
3
Itai nyan~
Ninjin wa iyadanyan~
uhhh nyan~
Sample Output 1:
nyan~
Sample Input 2:
3
Itai!
Ninjinnwaiyada T_T
T_T
Sample Output 2:

nai

IDEA
1.找各string的最大公共后缀字符串，先翻转，再遍历

CODE

#include<iostream>
#include<vector> 
#include<cstring>
#include<algorithm>
#include<fstream>
using namespace std;
int main(){
	#ifndef ONLINE_JUDGE
	freopen("input.txt","r",stdin);
	#endif
	
	int n;
	cin>>n;
	getchar();
	vector<string> vec;
	string str,result="";
	while(n--){
		getline(cin,str);
		reverse(str.begin(),str.end());
		vec.push_back(str);
	}
	
	str=vec[0];
	for(int i=0;i<str.size();i++){
		int flag=1;
		for(int j=1;j<vec.size();j++){
			if(str[i]!=vec[j][i]){
				flag=0;
				break;
			}
		}
		if(flag){
			result=str[i]+result;
		}else{
			break;
		}
		
	}
	if(result==""){
		cout<<"nai"<<endl;
	}else{	
		cout<<result<<endl;
	}
	
	#ifndef ONLINE_JUDGE
	fclose(stdin);
	#endif
	return 0;
}