#include<bits/stdc++.h>
using namespace std;
const int N = 2000009, Mod = 1e9 + 9;
int n, P[N], H[N];
char A[N];
inline int GetHash(int l, int r)
{
return (H[r] - H[l - 1] * 1LL * P[r - l + 1] % Mod + Mod) % Mod;
}
int main()
{
scanf("%d%s", &n, A + 1);
if (n % 2 == 0)
return !printf("NOT POSSIBLE\n");
for (int i = P[0] = 1; i < N; i++)
P[i] = P[i - 1] * 791LL % Mod;
for (int i = 1; i <= n; i++)
H[i] = (H[i - 1] + A[i]) * 791LL % Mod;
int len = n >> 1, HSH = -1;
for (int i = 1; i <= n; i++)
{
int hsh1, hsh2;
if (i <= len)
{
hsh1 = (GetHash(1, i - 1) * 1LL * P[len - (i - 1)] + GetHash(i + 1, len + 1)) % Mod;
hsh2 = GetHash(n - len + 1, n);
}
else
{
hsh1 = GetHash(1, len);
hsh2 = (GetHash(len + 1, i - 1) * 1LL * P[len - (i - len - 1)] + GetHash(i + 1, n)) % Mod;
}
if (hsh1 != hsh2)
continue;
if (HSH == -1)
HSH = hsh1;
if (hsh1 != HSH)
return !printf("NOT UNIQUE\n");
}
for (int i = 1; i <= n; i++)
if (GetHash(i, i + len - 1) == HSH)
{
A[i + len] = 0;
printf("%s\n", A + i);
return 0;
}
return !printf("NOT POSSIBLE\n");
}
Compilation message
friends.cpp: In function 'int main()':
friends.cpp:12:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf("%d%s", &n, A + 1);
~~~~~^~~~~~~~~~~~~~~~~~~
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
20 ms |
8184 KB |
Output is correct |
2 |
Correct |
21 ms |
8184 KB |
Output is correct |
3 |
Correct |
19 ms |
8184 KB |
Output is correct |
4 |
Correct |
21 ms |
8184 KB |
Output is correct |
5 |
Correct |
20 ms |
8192 KB |
Output is correct |
6 |
Correct |
20 ms |
8100 KB |
Output is correct |
7 |
Correct |
20 ms |
8192 KB |
Output is correct |
8 |
Correct |
21 ms |
8192 KB |
Output is correct |
9 |
Correct |
20 ms |
8192 KB |
Output is correct |
10 |
Correct |
22 ms |
8184 KB |
Output is correct |
11 |
Correct |
20 ms |
8192 KB |
Output is correct |
12 |
Correct |
21 ms |
8192 KB |
Output is correct |
13 |
Correct |
21 ms |
8160 KB |
Output is correct |
14 |
Correct |
20 ms |
8192 KB |
Output is correct |
15 |
Correct |
21 ms |
8240 KB |
Output is correct |
16 |
Correct |
20 ms |
8184 KB |
Output is correct |
17 |
Correct |
22 ms |
8184 KB |
Output is correct |
18 |
Correct |
21 ms |
8192 KB |
Output is correct |
19 |
Correct |
20 ms |
8192 KB |
Output is correct |
20 |
Correct |
22 ms |
8192 KB |
Output is correct |
21 |
Correct |
20 ms |
8184 KB |
Output is correct |
22 |
Correct |
20 ms |
8184 KB |
Output is correct |
23 |
Correct |
20 ms |
8312 KB |
Output is correct |
24 |
Correct |
2 ms |
256 KB |
Output is correct |
25 |
Correct |
2 ms |
356 KB |
Output is correct |
26 |
Correct |
2 ms |
384 KB |
Output is correct |
27 |
Correct |
19 ms |
8192 KB |
Output is correct |
28 |
Correct |
20 ms |
8168 KB |
Output is correct |
29 |
Correct |
19 ms |
8184 KB |
Output is correct |
30 |
Correct |
21 ms |
8192 KB |
Output is correct |
31 |
Correct |
21 ms |
8064 KB |
Output is correct |
32 |
Correct |
20 ms |
8228 KB |
Output is correct |
33 |
Correct |
20 ms |
8192 KB |
Output is correct |
34 |
Correct |
23 ms |
8184 KB |
Output is correct |
35 |
Correct |
20 ms |
8192 KB |
Output is correct |
36 |
Correct |
20 ms |
8192 KB |
Output is correct |
37 |
Correct |
22 ms |
8192 KB |
Output is correct |
38 |
Correct |
19 ms |
8148 KB |
Output is correct |
39 |
Correct |
20 ms |
8192 KB |
Output is correct |
40 |
Correct |
21 ms |
8164 KB |
Output is correct |
41 |
Correct |
21 ms |
8192 KB |
Output is correct |
42 |
Correct |
20 ms |
8184 KB |
Output is correct |
43 |
Correct |
20 ms |
8192 KB |
Output is correct |
44 |
Correct |
20 ms |
8192 KB |
Output is correct |
45 |
Correct |
20 ms |
8192 KB |
Output is correct |
46 |
Correct |
20 ms |
8192 KB |
Output is correct |
47 |
Correct |
22 ms |
8184 KB |
Output is correct |
48 |
Correct |
21 ms |
8192 KB |
Output is correct |
49 |
Correct |
2 ms |
384 KB |
Output is correct |
50 |
Correct |
20 ms |
8192 KB |
Output is correct |
51 |
Correct |
19 ms |
8252 KB |
Output is correct |
52 |
Correct |
21 ms |
8192 KB |
Output is correct |
53 |
Correct |
21 ms |
8164 KB |
Output is correct |
54 |
Correct |
20 ms |
8144 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
189 ms |
20920 KB |
Output is correct |
2 |
Correct |
165 ms |
20904 KB |
Output is correct |
3 |
Correct |
184 ms |
20984 KB |
Output is correct |
4 |
Correct |
171 ms |
20920 KB |
Output is correct |
5 |
Correct |
156 ms |
20856 KB |
Output is correct |
6 |
Correct |
15 ms |
4300 KB |
Output is correct |
7 |
Correct |
151 ms |
20920 KB |
Output is correct |
8 |
Correct |
143 ms |
18920 KB |
Output is correct |
9 |
Correct |
144 ms |
19548 KB |
Output is correct |
10 |
Correct |
157 ms |
19832 KB |
Output is correct |
11 |
Correct |
148 ms |
18044 KB |
Output is correct |
12 |
Correct |
19 ms |
8188 KB |
Output is correct |
13 |
Correct |
19 ms |
8192 KB |
Output is correct |
14 |
Correct |
20 ms |
8192 KB |
Output is correct |
15 |
Correct |
19 ms |
8192 KB |
Output is correct |
16 |
Correct |
19 ms |
8192 KB |
Output is correct |
17 |
Correct |
20 ms |
8192 KB |
Output is correct |
18 |
Correct |
21 ms |
8180 KB |
Output is correct |
19 |
Correct |
19 ms |
8192 KB |
Output is correct |
20 |
Correct |
20 ms |
8196 KB |
Output is correct |
21 |
Correct |
20 ms |
8192 KB |
Output is correct |
22 |
Correct |
17 ms |
8184 KB |
Output is correct |
23 |
Correct |
20 ms |
8192 KB |
Output is correct |
24 |
Correct |
20 ms |
8184 KB |
Output is correct |
25 |
Correct |
22 ms |
8192 KB |
Output is correct |
26 |
Correct |
21 ms |
8184 KB |
Output is correct |
27 |
Correct |
22 ms |
8184 KB |
Output is correct |
28 |
Correct |
20 ms |
8164 KB |
Output is correct |
29 |
Correct |
20 ms |
8184 KB |
Output is correct |
30 |
Correct |
19 ms |
8184 KB |
Output is correct |
31 |
Correct |
20 ms |
8188 KB |
Output is correct |
32 |
Correct |
20 ms |
8184 KB |
Output is correct |
33 |
Correct |
19 ms |
8192 KB |
Output is correct |
34 |
Correct |
19 ms |
8184 KB |
Output is correct |
35 |
Correct |
2 ms |
384 KB |
Output is correct |
36 |
Correct |
2 ms |
256 KB |
Output is correct |
37 |
Correct |
3 ms |
384 KB |
Output is correct |
38 |
Correct |
20 ms |
8184 KB |
Output is correct |
39 |
Correct |
21 ms |
8192 KB |
Output is correct |
40 |
Correct |
23 ms |
8192 KB |
Output is correct |
41 |
Correct |
21 ms |
8156 KB |
Output is correct |
42 |
Correct |
20 ms |
8192 KB |
Output is correct |
43 |
Correct |
20 ms |
8192 KB |
Output is correct |
44 |
Correct |
20 ms |
8184 KB |
Output is correct |
45 |
Correct |
21 ms |
8320 KB |
Output is correct |
46 |
Correct |
20 ms |
8184 KB |
Output is correct |
47 |
Correct |
20 ms |
8160 KB |
Output is correct |
48 |
Correct |
20 ms |
8192 KB |
Output is correct |
49 |
Correct |
19 ms |
8192 KB |
Output is correct |
50 |
Correct |
20 ms |
8192 KB |
Output is correct |
51 |
Correct |
20 ms |
8192 KB |
Output is correct |
52 |
Correct |
21 ms |
8184 KB |
Output is correct |
53 |
Correct |
17 ms |
8192 KB |
Output is correct |
54 |
Correct |
20 ms |
8176 KB |
Output is correct |