#include <iostream>
#include <set>
using namespace std;
#define ll long long
const ll N=2e6+2;
ll pre[N],pw[N],base=717,mod=1e9+9;
int get(int l,int r)// one base indexing 1<=l<=n
{
if(r<l)
return 0;
return ((pre[r]-(pre[l-1]*pw[r-l+1])%mod)%mod+mod)%mod;
}
int main()
{
int n;
cin>>n;
string s;
cin>>s;
pre[0]=0;
pw[0]=1;
for(int i=1;i<=n;i++)
pw[i]=(pw[i-1]*base)%mod;
for(int i=1;i<=n;i++)
pre[i]=((pre[i-1]*base)%mod+(s[i-1]-'A'))%mod;
set<int> posa,pp;
int len=(n-1)/2;
for(int i=1;(n%2==1) and i<=n and posa.size()<2;i++)
{
ll fit=0;
ll sec=0;
int lf=(i-1);
if(lf<=len)
{
fit=((get(1,i-1)*pw[len-lf])%mod+get(i+1,i+len-lf))%mod;
sec=get(i+len-lf+1,n);
}
else{
fit=get(1,len);
sec=((get(len+1,i-1)*pw[n-i])%mod + get(i+1,n))%mod;
}
if(fit==sec)
{
posa.insert(i);
pp.insert(i);
}
}
if(posa.size()==0 or n%2!=1)
{
cout<<"NOT POSSIBLE\n";
}
else if(posa.size()==1)
{
int j=*begin(posa);
for(int i=1,p=0;p<len;i++)
{
if(i!=j)
{
cout<<s[i-1];
p++;
}
}
cout<<'\n';
}
else{
cout<<"NOT UNIQUE\n";
}
return 0;
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
1 ms |
2392 KB |
Output is correct |
2 |
Correct |
0 ms |
2648 KB |
Output is correct |
3 |
Correct |
1 ms |
2396 KB |
Output is correct |
4 |
Correct |
1 ms |
2396 KB |
Output is correct |
5 |
Correct |
1 ms |
2396 KB |
Output is correct |
6 |
Correct |
0 ms |
2396 KB |
Output is correct |
7 |
Correct |
1 ms |
2396 KB |
Output is correct |
8 |
Correct |
1 ms |
2396 KB |
Output is correct |
9 |
Correct |
1 ms |
2392 KB |
Output is correct |
10 |
Correct |
1 ms |
2396 KB |
Output is correct |
11 |
Correct |
0 ms |
2396 KB |
Output is correct |
12 |
Correct |
0 ms |
2396 KB |
Output is correct |
13 |
Correct |
1 ms |
2396 KB |
Output is correct |
14 |
Correct |
1 ms |
2648 KB |
Output is correct |
15 |
Correct |
0 ms |
2396 KB |
Output is correct |
16 |
Correct |
1 ms |
2396 KB |
Output is correct |
17 |
Correct |
1 ms |
2392 KB |
Output is correct |
18 |
Correct |
0 ms |
2396 KB |
Output is correct |
19 |
Correct |
0 ms |
2396 KB |
Output is correct |
20 |
Correct |
0 ms |
2392 KB |
Output is correct |
21 |
Correct |
1 ms |
2396 KB |
Output is correct |
22 |
Correct |
0 ms |
2396 KB |
Output is correct |
23 |
Correct |
0 ms |
2396 KB |
Output is correct |
24 |
Correct |
0 ms |
2396 KB |
Output is correct |
25 |
Correct |
1 ms |
2396 KB |
Output is correct |
26 |
Correct |
0 ms |
2396 KB |
Output is correct |
27 |
Correct |
0 ms |
2396 KB |
Output is correct |
28 |
Correct |
1 ms |
2396 KB |
Output is correct |
29 |
Correct |
0 ms |
2492 KB |
Output is correct |
30 |
Correct |
0 ms |
2648 KB |
Output is correct |
31 |
Correct |
0 ms |
2396 KB |
Output is correct |
32 |
Correct |
0 ms |
2396 KB |
Output is correct |
33 |
Correct |
1 ms |
2396 KB |
Output is correct |
34 |
Correct |
0 ms |
2396 KB |
Output is correct |
35 |
Correct |
1 ms |
2548 KB |
Output is correct |
36 |
Correct |
1 ms |
2396 KB |
Output is correct |
37 |
Correct |
0 ms |
2396 KB |
Output is correct |
38 |
Correct |
1 ms |
2396 KB |
Output is correct |
39 |
Correct |
1 ms |
2396 KB |
Output is correct |
40 |
Correct |
1 ms |
2396 KB |
Output is correct |
41 |
Correct |
1 ms |
2396 KB |
Output is correct |
42 |
Correct |
0 ms |
2396 KB |
Output is correct |
43 |
Correct |
1 ms |
2648 KB |
Output is correct |
44 |
Correct |
1 ms |
2396 KB |
Output is correct |
45 |
Correct |
1 ms |
2396 KB |
Output is correct |
46 |
Correct |
1 ms |
2396 KB |
Output is correct |
47 |
Correct |
1 ms |
2396 KB |
Output is correct |
48 |
Correct |
1 ms |
2396 KB |
Output is correct |
49 |
Correct |
1 ms |
2396 KB |
Output is correct |
50 |
Incorrect |
0 ms |
2396 KB |
Output isn't correct |
51 |
Halted |
0 ms |
0 KB |
- |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
207 ms |
36096 KB |
Output is correct |
2 |
Correct |
206 ms |
35240 KB |
Output is correct |
3 |
Correct |
205 ms |
35772 KB |
Output is correct |
4 |
Correct |
205 ms |
34968 KB |
Output is correct |
5 |
Incorrect |
89 ms |
34748 KB |
Output isn't correct |
6 |
Halted |
0 ms |
0 KB |
- |