PAT-A 1077. Kuchiguse (20)（20 分）

https://pintia.cn/problem-sets/994805342720868352/problems/994805390896644096

1077 Kuchiguse (20)（20 分）提问

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

注意：

scanf或者cin后，一定要getchar()

#include <iostream>
#include<string> 
#include<algorithm>
using namespace std;

int main(int argc, char** argv) {
    int n;
    cin>>n;
    //scanf("%d",&n);
    getchar();
    string ans;
    for(int i=0;i<n;i++){
    	string s;
    	getline(cin,s);
    	int len=s.length();
    	reverse(s.begin(),s.end());
    	if(i==0){
    		ans=s;
    		continue;
		}else{
			int lenans=ans.length();
			int minlen=min(len,lenans);
			for(int j=0;j<minlen;j++){//每次与前面保存的ans比较 
				if(s[j]!=ans[j]){
					ans=ans.substr(0,j);
					break;
				}
			}
		}
	}
	reverse(ans.begin(),ans.end());
	if(ans.length()==0){
		ans="nai";
	}
	cout<<ans;
	
	return 0;
}