愉快的补题解1 CodeForces - 877A Alex and broken contest 大大大大大水题

One day Alex was creating a contest about his friends, but accidentally deleted it. Fortunately, all the problems were saved, but now he needs to find them among other problems.

But there are too many problems, to do it manually. Alex asks you to write a program, which will determine if a problem is from this contest by its name.

It is known, that problem is from this contest if and only if its name contains one of Alex’s friends’ name exactly once. His friends’ names are “Danil”, “Olya”, “Slava”, “Ann” and “Nikita”.

Names are case sensitive.

Input
The only line contains string from lowercase and uppercase letters and “_” symbols of length, not more than 100 — the name of the problem.

Output
Print “YES”, if problem is from this contest, and “NO” otherwise.

Examples
Input
Alex_and_broken_contest
Output
NO

Input
NikitaAndString
Output
YES
Input
Danil_and_Olya
Output
NO

题目大意：给出一个串，若串中只包含一个已知串便满足规则。
思路：一共只有100个字符，以每个字符为起点，遍历即可。

AC代码：

#include<cstdio>
#include<iostream>
#include<string>
#include<cstring>

using namespace std;
 
string str[5] = {"Danil", "Olya", "Slava", "Ann" , "Nikita"};
 
string S;
 
int main(){
	while (cin >> S){
		int num = 0;
		for (int i = 0; i < 5; i++) {
			for (int j = 0; j < S.size(); j++) {
				if (S.substr(j, str[i].size()) == str[i])
					num++;
			}
		}
		if (num == 1){
			cout<<"YES\n";
		}else{
			cout<<"NO\n";
		}
	}
	return 0;
}