#include <bits/stdc++.h>
#define sz(x) ((int)x.size())
#define all(x) (x).begin(), (x).end()
#define fi first
#define se second
using namespace std;
typedef long long ll;
typedef long double ld;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
int n;
char s[2000010];
bool multi;
string solve() {
string ret="";
int i,j=-1,cnt=0; bool chk=true;
for(i=0;i<=n/2;i++) {
cnt+=s[i]==s[i+n/2];
}
for(i=0;i<=n/2;i++) {
cnt-=s[i]==s[i+n/2];
if(cnt==n/2) {
if(j!=-1) {
//s[j]==s[j+1],s[j+1]==s[j+2],...,s[i-1]==s[i]
if(!chk) {
multi=true;
break;
}
}
j=i;
chk=true;
}
cnt+=s[i]==s[i+n/2+1];
chk&=s[i]==s[i+1];
}
if(j==-1) return ret;
for(i=0;i<n;i++) {
if(i==j)continue;
ret+=s[i];
}
ret.erase(ret.begin()+n/2,ret.end());
return ret;
}
int main() {
scanf("%d%s",&n,s);
if(n%2==0){
puts("NOT POSSIBLE");
return 0;
}
int i;
string a=solve();
if(multi) {
puts("NOT UNIQUE");
return 0;
}
for(i=0;i<n/2;i++) swap(s[i],s[n-i-1]);
string b=solve();
if(multi) {
puts("NOT UNIQUE");
return 0;
}
reverse(b.begin(),b.end());
if(a.empty() && b.empty()) {
puts("NOT POSSIBLE");
} else if(a.empty()) {
printf("%s",b.c_str());
} else if(b.empty()) {
printf("%s", a.c_str());
} else {
if(a==b) printf("%s",a.c_str());
else puts("NOT UNIQUE");
}
return 0;
}
Compilation message
friends.cpp: In function 'int main()':
friends.cpp:45:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf("%d%s",&n,s);
~~~~~^~~~~~~~~~~~~
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
2 ms |
504 KB |
Output is correct |
2 |
Correct |
2 ms |
256 KB |
Output is correct |
3 |
Correct |
2 ms |
256 KB |
Output is correct |
4 |
Correct |
2 ms |
256 KB |
Output is correct |
5 |
Correct |
2 ms |
376 KB |
Output is correct |
6 |
Correct |
2 ms |
256 KB |
Output is correct |
7 |
Correct |
2 ms |
256 KB |
Output is correct |
8 |
Correct |
2 ms |
256 KB |
Output is correct |
9 |
Correct |
2 ms |
256 KB |
Output is correct |
10 |
Correct |
2 ms |
376 KB |
Output is correct |
11 |
Correct |
2 ms |
256 KB |
Output is correct |
12 |
Correct |
2 ms |
376 KB |
Output is correct |
13 |
Correct |
2 ms |
256 KB |
Output is correct |
14 |
Correct |
2 ms |
380 KB |
Output is correct |
15 |
Correct |
2 ms |
376 KB |
Output is correct |
16 |
Correct |
2 ms |
256 KB |
Output is correct |
17 |
Correct |
2 ms |
256 KB |
Output is correct |
18 |
Correct |
2 ms |
256 KB |
Output is correct |
19 |
Correct |
2 ms |
256 KB |
Output is correct |
20 |
Correct |
2 ms |
256 KB |
Output is correct |
21 |
Correct |
2 ms |
252 KB |
Output is correct |
22 |
Correct |
2 ms |
376 KB |
Output is correct |
23 |
Correct |
2 ms |
252 KB |
Output is correct |
24 |
Correct |
2 ms |
376 KB |
Output is correct |
25 |
Correct |
2 ms |
376 KB |
Output is correct |
26 |
Correct |
2 ms |
376 KB |
Output is correct |
27 |
Correct |
2 ms |
376 KB |
Output is correct |
28 |
Correct |
2 ms |
376 KB |
Output is correct |
29 |
Correct |
2 ms |
256 KB |
Output is correct |
30 |
Correct |
2 ms |
256 KB |
Output is correct |
31 |
Correct |
2 ms |
376 KB |
Output is correct |
32 |
Correct |
2 ms |
376 KB |
Output is correct |
33 |
Correct |
2 ms |
376 KB |
Output is correct |
34 |
Correct |
2 ms |
376 KB |
Output is correct |
35 |
Correct |
2 ms |
380 KB |
Output is correct |
36 |
Correct |
2 ms |
376 KB |
Output is correct |
37 |
Correct |
2 ms |
256 KB |
Output is correct |
38 |
Correct |
2 ms |
380 KB |
Output is correct |
39 |
Correct |
2 ms |
256 KB |
Output is correct |
40 |
Correct |
2 ms |
256 KB |
Output is correct |
41 |
Correct |
2 ms |
376 KB |
Output is correct |
42 |
Correct |
2 ms |
252 KB |
Output is correct |
43 |
Correct |
2 ms |
256 KB |
Output is correct |
44 |
Correct |
2 ms |
376 KB |
Output is correct |
45 |
Correct |
2 ms |
376 KB |
Output is correct |
46 |
Correct |
2 ms |
380 KB |
Output is correct |
47 |
Correct |
2 ms |
376 KB |
Output is correct |
48 |
Correct |
2 ms |
376 KB |
Output is correct |
49 |
Correct |
2 ms |
256 KB |
Output is correct |
50 |
Correct |
2 ms |
376 KB |
Output is correct |
51 |
Correct |
2 ms |
376 KB |
Output is correct |
52 |
Correct |
2 ms |
376 KB |
Output is correct |
53 |
Correct |
2 ms |
256 KB |
Output is correct |
54 |
Correct |
2 ms |
256 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
38 ms |
8480 KB |
Output is correct |
2 |
Correct |
37 ms |
8168 KB |
Output is correct |
3 |
Correct |
37 ms |
8196 KB |
Output is correct |
4 |
Correct |
36 ms |
8168 KB |
Output is correct |
5 |
Correct |
37 ms |
8152 KB |
Output is correct |
6 |
Correct |
10 ms |
4216 KB |
Output is correct |
7 |
Correct |
56 ms |
12004 KB |
Output is correct |
8 |
Correct |
46 ms |
8556 KB |
Output is correct |
9 |
Correct |
33 ms |
6636 KB |
Output is correct |
10 |
Correct |
32 ms |
6636 KB |
Output is correct |
11 |
Correct |
15 ms |
3576 KB |
Output is correct |
12 |
Correct |
2 ms |
256 KB |
Output is correct |
13 |
Correct |
2 ms |
256 KB |
Output is correct |
14 |
Correct |
2 ms |
256 KB |
Output is correct |
15 |
Correct |
2 ms |
376 KB |
Output is correct |
16 |
Correct |
2 ms |
256 KB |
Output is correct |
17 |
Correct |
2 ms |
376 KB |
Output is correct |
18 |
Correct |
2 ms |
376 KB |
Output is correct |
19 |
Correct |
2 ms |
376 KB |
Output is correct |
20 |
Correct |
2 ms |
256 KB |
Output is correct |
21 |
Correct |
2 ms |
376 KB |
Output is correct |
22 |
Correct |
2 ms |
376 KB |
Output is correct |
23 |
Correct |
2 ms |
256 KB |
Output is correct |
24 |
Correct |
2 ms |
256 KB |
Output is correct |
25 |
Correct |
2 ms |
376 KB |
Output is correct |
26 |
Correct |
2 ms |
376 KB |
Output is correct |
27 |
Correct |
2 ms |
376 KB |
Output is correct |
28 |
Correct |
2 ms |
376 KB |
Output is correct |
29 |
Correct |
2 ms |
256 KB |
Output is correct |
30 |
Correct |
2 ms |
256 KB |
Output is correct |
31 |
Correct |
2 ms |
376 KB |
Output is correct |
32 |
Correct |
2 ms |
376 KB |
Output is correct |
33 |
Correct |
2 ms |
256 KB |
Output is correct |
34 |
Correct |
2 ms |
252 KB |
Output is correct |
35 |
Correct |
2 ms |
376 KB |
Output is correct |
36 |
Correct |
2 ms |
376 KB |
Output is correct |
37 |
Correct |
2 ms |
376 KB |
Output is correct |
38 |
Correct |
2 ms |
256 KB |
Output is correct |
39 |
Correct |
2 ms |
256 KB |
Output is correct |
40 |
Correct |
3 ms |
376 KB |
Output is correct |
41 |
Correct |
2 ms |
368 KB |
Output is correct |
42 |
Correct |
2 ms |
376 KB |
Output is correct |
43 |
Correct |
2 ms |
376 KB |
Output is correct |
44 |
Correct |
2 ms |
376 KB |
Output is correct |
45 |
Correct |
2 ms |
376 KB |
Output is correct |
46 |
Correct |
2 ms |
256 KB |
Output is correct |
47 |
Correct |
2 ms |
256 KB |
Output is correct |
48 |
Correct |
2 ms |
256 KB |
Output is correct |
49 |
Correct |
2 ms |
376 KB |
Output is correct |
50 |
Correct |
2 ms |
252 KB |
Output is correct |
51 |
Correct |
2 ms |
376 KB |
Output is correct |
52 |
Correct |
2 ms |
376 KB |
Output is correct |
53 |
Correct |
2 ms |
376 KB |
Output is correct |
54 |
Correct |
2 ms |
376 KB |
Output is correct |