Submission #98426

# Submission time Handle Problem Language Result Execution time Memory
98426 2019-02-23T13:51:18 Z Kastanda Three Friends (BOI14_friends) C++11
100 / 100
189 ms 20984 KB
#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