5.20

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

int main()
{
	string read, tmp;
	int flag = 0;
	while (cin >> read)
	{
		if (read == tmp)
		{
			flag = 1;
			break;
		}
		else tmp = read;
	}
	if (flag)
		cout << read << " occurs twice in succession" << endl;
	else cout << "no word was repeated" << endl;
	return 0;
}