Submission #240577

#	Time	Username	Problem	Language	Result	Execution time	Memory
240577		Goolakh	Three Friends (BOI14_friends)	C++17	100 / 100	35 ms	7168 KiB

friends

#include <bits/stdc++.h>
using namespace std;
 
#pragma GCC optimize("O2,no-stack-protector,unroll-loops,fast-math")
//#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
//#pragma GCC optimize("Os")
 
#define F first
#define S second
#define pb push_back
#define SZ(x) (ll)(x.size())
#define all(x) x.begin(),x.end()
//#define mp make_pair
 
typedef long long ll;
typedef long double ld;
typedef pair<ll,ll> pll;
 
//mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
 
const ll maxn=2e6+10, maxm=2e3+10, lg=22, mod=1e9+9, inf=1e18;
 
int n,i,j;
string s,t,ans;
map<string,bool> mp;
 
int main(){
	ios_base::sync_with_stdio(0),cin.tie(0),cout.tie(0);
	
	cin>>n;
	cin>>s; s='#'+s;
	if(n%2==0) return cout<<"NOT POSSIBLE",0;
	for(i=1,j=0;i<=n/2;i++) t+=s[i];
	for(;i<=n;i++) j+=(s[i]==t[j]);
	if(j==n/2) mp[ans=t]=1;
	for(t="",i=(n/2)+2;i<=n;i++) t+=s[i];
	for(i=1,j=0;i<=n/2+1;i++) j+=(s[i]==t[j]);
	if(j==n/2) mp[ans=t]=1;
	if(mp.empty()) cout<<"NOT POSSIBLE";
	else if(SZ(mp)>1) cout<<"NOT UNIQUE";
	else cout<<ans;
	
	return 0;
}

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