#include <bits/stdc++.h>
using namespace std;
#define int long long
main(){
ios_base::sync_with_stdio(0); cin.tie(0);
int n;
cin >> n;
if (n % 2 == 0) {cout << "NOT POSSIBLE"; return 0;}
string s; cin >> s;
set<string> ans;
string ls = "", rs = "";
for (int x = 0; x < n/2; x++) ls.push_back(s[x]);
for (int x = n/2 + 1; x < n; x++) rs.push_back(s[x]);
if (ls == rs){
ans.insert(ls);
}
string lcomp = ls, rcomp = rs;
ls.push_back(s[n/2]);
rs = s[n/2] + rs;
bool lprepass[n]; memset(lprepass, 0, sizeof(lprepass));
bool lpostpass[n]; memset(lpostpass, 0, sizeof(lpostpass));
for (int x = 0; x < n/2; x++){
if (ls[x] == rcomp[x]){
lprepass[x] = 1;
}
else break;
}
for (int x = n/2+1; x > 0; x--){
if (ls[x] == rcomp[x-1]){
lpostpass[x] = 1;
}
else break;
}
if (lpostpass[1]) ans.insert(rcomp);
for (int x = 0; x < n/2; x++){
if (lprepass[x] && lpostpass[x+2]){
ans.insert(rcomp);
break;
}
}
if (lprepass[n/2 - 1]) ans.insert(rcomp);
bool rprepass[n]; memset(rprepass, 0, sizeof(rprepass));
bool rpostpass[n]; memset(rpostpass, 0, sizeof(rpostpass));
for (int x = 0; x < n/2; x++){
if (rs[x] == lcomp[x]){
rprepass[x] = 1;
}
else break;
}
for (int x = n/2+1; x > 0; x--){
if (rs[x] == lcomp[x-1]){
rpostpass[x] = 1;
}
else break;
}
if (rpostpass[1]) ans.insert(lcomp);
for (int x = 0; x < n/2; x++){
if (rprepass[x] && rpostpass[x+2]){
ans.insert(lcomp);
break;
}
}
if (rprepass[n/2 - 1]) ans.insert(lcomp);
if (ans.size() == 0) cout << "NOT POSSIBLE";
else if (ans.size() == 1) cout << *ans.begin();
else cout << "NOT UNIQUE";
}
Compilation message
friends.cpp:6:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
6 | main(){
| ^~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
0 ms |
348 KB |
Output is correct |
| 2 |
Correct |
0 ms |
348 KB |
Output is correct |
| 3 |
Correct |
0 ms |
348 KB |
Output is correct |
| 4 |
Correct |
0 ms |
348 KB |
Output is correct |
| 5 |
Correct |
0 ms |
348 KB |
Output is correct |
| 6 |
Correct |
0 ms |
348 KB |
Output is correct |
| 7 |
Correct |
0 ms |
348 KB |
Output is correct |
| 8 |
Correct |
0 ms |
348 KB |
Output is correct |
| 9 |
Correct |
0 ms |
460 KB |
Output is correct |
| 10 |
Correct |
0 ms |
348 KB |
Output is correct |
| 11 |
Correct |
1 ms |
344 KB |
Output is correct |
| 12 |
Correct |
0 ms |
348 KB |
Output is correct |
| 13 |
Correct |
0 ms |
348 KB |
Output is correct |
| 14 |
Correct |
0 ms |
348 KB |
Output is correct |
| 15 |
Correct |
0 ms |
460 KB |
Output is correct |
| 16 |
Correct |
0 ms |
348 KB |
Output is correct |
| 17 |
Correct |
1 ms |
348 KB |
Output is correct |
| 18 |
Correct |
0 ms |
348 KB |
Output is correct |
| 19 |
Correct |
1 ms |
348 KB |
Output is correct |
| 20 |
Correct |
0 ms |
348 KB |
Output is correct |
| 21 |
Correct |
1 ms |
344 KB |
Output is correct |
| 22 |
Correct |
0 ms |
348 KB |
Output is correct |
| 23 |
Correct |
0 ms |
348 KB |
Output is correct |
| 24 |
Correct |
0 ms |
348 KB |
Output is correct |
| 25 |
Correct |
1 ms |
348 KB |
Output is correct |
| 26 |
Correct |
0 ms |
348 KB |
Output is correct |
| 27 |
Correct |
1 ms |
456 KB |
Output is correct |
| 28 |
Correct |
0 ms |
348 KB |
Output is correct |
| 29 |
Correct |
0 ms |
348 KB |
Output is correct |
| 30 |
Correct |
0 ms |
348 KB |
Output is correct |
| 31 |
Correct |
0 ms |
348 KB |
Output is correct |
| 32 |
Correct |
0 ms |
456 KB |
Output is correct |
| 33 |
Correct |
0 ms |
348 KB |
Output is correct |
| 34 |
Correct |
0 ms |
348 KB |
Output is correct |
| 35 |
Correct |
0 ms |
348 KB |
Output is correct |
| 36 |
Correct |
0 ms |
348 KB |
Output is correct |
| 37 |
Correct |
0 ms |
348 KB |
Output is correct |
| 38 |
Correct |
0 ms |
452 KB |
Output is correct |
| 39 |
Correct |
1 ms |
344 KB |
Output is correct |
| 40 |
Correct |
0 ms |
348 KB |
Output is correct |
| 41 |
Correct |
1 ms |
348 KB |
Output is correct |
| 42 |
Correct |
0 ms |
348 KB |
Output is correct |
| 43 |
Correct |
0 ms |
348 KB |
Output is correct |
| 44 |
Correct |
0 ms |
348 KB |
Output is correct |
| 45 |
Correct |
0 ms |
348 KB |
Output is correct |
| 46 |
Correct |
1 ms |
456 KB |
Output is correct |
| 47 |
Correct |
0 ms |
348 KB |
Output is correct |
| 48 |
Correct |
0 ms |
348 KB |
Output is correct |
| 49 |
Correct |
0 ms |
348 KB |
Output is correct |
| 50 |
Correct |
0 ms |
344 KB |
Output is correct |
| 51 |
Correct |
0 ms |
348 KB |
Output is correct |
| 52 |
Correct |
0 ms |
348 KB |
Output is correct |
| 53 |
Correct |
0 ms |
348 KB |
Output is correct |
| 54 |
Correct |
0 ms |
348 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
18 ms |
17320 KB |
Output is correct |
| 2 |
Correct |
16 ms |
17196 KB |
Output is correct |
| 3 |
Correct |
16 ms |
17108 KB |
Output is correct |
| 4 |
Correct |
17 ms |
17204 KB |
Output is correct |
| 5 |
Correct |
16 ms |
17192 KB |
Output is correct |
| 6 |
Correct |
1 ms |
348 KB |
Output is correct |
| 7 |
Correct |
17 ms |
17192 KB |
Output is correct |
| 8 |
Correct |
15 ms |
15716 KB |
Output is correct |
| 9 |
Correct |
15 ms |
15832 KB |
Output is correct |
| 10 |
Correct |
14 ms |
15860 KB |
Output is correct |
| 11 |
Correct |
13 ms |
13816 KB |
Output is correct |
| 12 |
Correct |
0 ms |
344 KB |
Output is correct |
| 13 |
Correct |
0 ms |
348 KB |
Output is correct |
| 14 |
Correct |
0 ms |
348 KB |
Output is correct |
| 15 |
Correct |
0 ms |
456 KB |
Output is correct |
| 16 |
Correct |
1 ms |
344 KB |
Output is correct |
| 17 |
Correct |
0 ms |
348 KB |
Output is correct |
| 18 |
Correct |
0 ms |
348 KB |
Output is correct |
| 19 |
Correct |
0 ms |
348 KB |
Output is correct |
| 20 |
Correct |
0 ms |
452 KB |
Output is correct |
| 21 |
Correct |
0 ms |
348 KB |
Output is correct |
| 22 |
Correct |
0 ms |
348 KB |
Output is correct |
| 23 |
Correct |
1 ms |
348 KB |
Output is correct |
| 24 |
Correct |
0 ms |
348 KB |
Output is correct |
| 25 |
Correct |
0 ms |
348 KB |
Output is correct |
| 26 |
Correct |
0 ms |
348 KB |
Output is correct |
| 27 |
Correct |
0 ms |
344 KB |
Output is correct |
| 28 |
Correct |
0 ms |
348 KB |
Output is correct |
| 29 |
Correct |
0 ms |
348 KB |
Output is correct |
| 30 |
Correct |
0 ms |
456 KB |
Output is correct |
| 31 |
Correct |
0 ms |
348 KB |
Output is correct |
| 32 |
Correct |
0 ms |
348 KB |
Output is correct |
| 33 |
Correct |
0 ms |
348 KB |
Output is correct |
| 34 |
Correct |
0 ms |
348 KB |
Output is correct |
| 35 |
Correct |
0 ms |
348 KB |
Output is correct |
| 36 |
Correct |
0 ms |
460 KB |
Output is correct |
| 37 |
Correct |
0 ms |
348 KB |
Output is correct |
| 38 |
Correct |
0 ms |
348 KB |
Output is correct |
| 39 |
Correct |
0 ms |
348 KB |
Output is correct |
| 40 |
Correct |
0 ms |
452 KB |
Output is correct |
| 41 |
Correct |
0 ms |
348 KB |
Output is correct |
| 42 |
Correct |
0 ms |
348 KB |
Output is correct |
| 43 |
Correct |
0 ms |
460 KB |
Output is correct |
| 44 |
Correct |
0 ms |
348 KB |
Output is correct |
| 45 |
Correct |
0 ms |
348 KB |
Output is correct |
| 46 |
Correct |
1 ms |
604 KB |
Output is correct |
| 47 |
Correct |
0 ms |
348 KB |
Output is correct |
| 48 |
Correct |
1 ms |
344 KB |
Output is correct |
| 49 |
Correct |
0 ms |
348 KB |
Output is correct |
| 50 |
Correct |
0 ms |
348 KB |
Output is correct |
| 51 |
Correct |
0 ms |
348 KB |
Output is correct |
| 52 |
Correct |
0 ms |
348 KB |
Output is correct |
| 53 |
Correct |
0 ms |
348 KB |
Output is correct |
| 54 |
Correct |
0 ms |
348 KB |
Output is correct |
