Submission #295092

#	Time	Username	Problem	Language	Result	Execution time	Memory
295092		Lawliet	Three Friends (BOI14_friends)	C++17	100 / 100	105 ms	8168 KiB

friends

#include <bits/stdc++.h>

using namespace std;

int n;

string s;

vector<string> ans;

void answer(string t)
{
	cout << t << endl;
	exit(0);
}

void test(string a, string b)
{
	int pA = 0, pB = 0;
	int qtdUnmatches = 0;

	while( pA < (int)a.size() && pB < (int)b.size() )
	{
		if( a[pA] == b[pB] ) pA++, pB++;
		else pB++, qtdUnmatches++;
	}

	if( qtdUnmatches > 1 ) return;

	if( ans.empty() || ans.back() != a )
		ans.push_back( a );
}

int main()
{
	cin >> n >> s;

	if( n%2 == 0 ) answer( "NOT POSSIBLE" );
	n /= 2;

	test( s.substr( 0 , n ) , s.substr( n , n + 1 ) );
	test( s.substr( n + 1 , n ) , s.substr( 0 , n + 1 ) );

	if( ans.empty() ) answer( "NOT POSSIBLE" );
	if( ans.size() == 1 ) answer( ans.back() );
	if( ans.size() == 2 ) answer( "NOT UNIQUE" );
}

• Subtask 1: 35 / 35
• Subtask 2: 65 / 65