Submission #106074

#	Time	Username	Problem	Language	Result	Execution time	Memory
106074		sofhiasouza	Three Friends (BOI14_friends)	C++14	0 / 100	1075 ms	8040 KiB

friends

#include <bits/stdc++.h>
#define pb push_back
using namespace std;
int main()
{
	int n, cont = -1, flag = 0;
	vector < int > vet;
	cin >> n;
	getchar();
	string s, s11 = "", s12 = "",s21 = "", s22 = "";
	cin >> s;
	if(n%2 == 0) flag = 0;
	else 
	{
		for(int i = 0 ; i < n ; i++)
		{
			if(i <= n/2) s11.pb(s[i]);
			else s21.pb(s[i]);
		}
		reverse(s11.begin(), s11.end());
		reverse(s21.begin(), s21.end());
		while(s11.size())
		{
			char k = s11[s11.size()-1];
			s11.pop_back();
			if(s11 == s21 and s12 == s22)
			{
				vet.pb((n/2 - s11.size()));
				flag = 1;
			}
			if(!s11.size()) continue;
			s12.pb(k);
			char k1 = s21[s21.size()-1];
			s21.pop_back();
			s22.pb(k1);
		}
 
		s11 = "", s12 = "",s21 = "", s22 = "";
		for(int i = 0 ; i < n ; i++)
		{
			if(i < n/2) s11.pb(s[i]);
			else s21.pb(s[i]);
		}
		reverse(s11.begin(), s11.end());
		reverse(s21.begin(), s21.end());
		while(s21.size())
		{
			char k = s21[s21.size()-1];
			s21.pop_back();
			if(s11 == s21 and s12 == s22)
			{
				vet.pb((n - 1 - s21.size()));
				flag = 1;
			}
			if(!s21.size()) continue;
			s22.pb(k);
			char k1 = s11[s11.size()-1];
			s11.pop_back();
			s12.pb(k1);
		}
	}
	if(flag == 0) cout << "NOT POSSIBLE\n";
	else
	{
		sort(vet.begin(), vet.end());
		string r1 = "", r2 = "", ante1 = "", ante2 = "";
		for(int i = 0 ; i < vet[0] ; i++) r1.pb(s[i]), ante1.pb(s[i]);
		for(int i = vet[0]+1 , j = r1.size()+1; j <= n/2 ; j++, i++) r2.pb(s[i]), ante2.pb(s[i]);
		reverse(r2.begin(), r2.end());
		reverse(ante2.begin(), ante2.end());
		
		for(int i = 1 ; i < vet.size() ; i++)
		{
			if(vet[i-1] != vet[i] and vet[i-1] < n/2)
			{
				r1.pb(vet[i-1]);
				ante1.pb(ante2[ante2.size()-1]);
				ante2.pop_back();
			}
			for(int j = vet[i-1]+1 ; j < vet[i] and ante2.size(); j++)
			{
				r1.pb(s[j]);
				ante1.pb(s[j]);
				r2.pop_back();
				ante2.pop_back();
			}
			if(ante2.size() != 0) ante2.pop_back();
			if(r1 == ante1 and r2 == ante2) flag = 1;
			else
			{
				flag = 2;
				break;
			}
		}
		if(flag == 1)
		{
			cout << ante1;
			reverse(ante2.begin(), ante2.end());
			cout << ante2 << endl;
		}
		else cout << "NOT UNIQUE\n";
	}
}

Compilation message (stderr)

friends.cpp: In function 'int main()':
friends.cpp:72:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for(int i = 1 ; i < vet.size() ; i++)
                   ~~^~~~~~~~~~~~
friends.cpp:6:9: warning: unused variable 'cont' [-Wunused-variable]
  int n, cont = -1, flag = 0;
         ^~~~

• Subtask 1: 0 / 35
• Subtask 2: 0 / 65