#include <bits/stdc++.h>
using namespace std;
using db = long double;
using ll = long long;
using pl = pair<ll, ll>;
using pi = pair<int, int>;
#define vt vector
#define f first
#define s second
#define pb push_back
#define all(x) x.begin(), x.end()
#define size(x) ((int) (x).size())
#define FOR(i, a, b) for (int i = (a); i < (b); i++)
#define ROF(i, a, b) for (int i = (b) - 1; i >= (a); i--)
#define F0R(i, b) FOR (i, 0, b)
#define endl '\n'
const ll INF = 1e18;
const int inf = 1e9;
/*
if a < b and b < c, then a < c
use string hashing
*/
const int m = 27;
const ll mod = 1e9 + 7;
const ll mx = 2e6 + 1;
ll powm[mx];
int n;
vt<vt<int>> adj;
vt<int> dp;
unordered_map<ll, int> seen;
void push_back(pl& hash, int c) {
hash = {(hash.f * m + c + 1) % mod, hash.s + 1};
}
void push_front(pl& hash, int c) {
hash = {(powm[hash.s] * (c + 1) + hash.f) % mod, hash.s + 1};
}
const pl hid = {0, 0};
int dfs(int u) {
if (dp[u] != -1) return dp[u];
int res = 0;
for (int v : adj[u]) {
res = max(res, dfs(v));
}
return dp[u] = res + 1;
}
main() {
cin.tie(0)->sync_with_stdio(0);
powm[0] = 1;
FOR (i, 1, mx) powm[i] = (powm[i - 1] * m) % mod;
cin >> n;
adj.resize(n);
dp.resize(n, -1);
F0R (i, n) {
pl lhs = hid, rhs = hid;
string st; cin >> st;
vt<int> a(size(st)); F0R (i, size(st)) a[i] = st[i] - 'A';
F0R (j, size(st)) {
push_back(lhs, a[j]);
push_front(rhs, a[size(st) - j - 1]);
if (lhs.f == rhs.f) {
auto it = seen.find(lhs.f);
if (it != seen.end()) {
adj[it->s].pb(i);
}
}
}
seen[lhs.f] = i;
}
F0R (i, n) dfs(i);
cout << *max_element(all(dp)) << endl;
}
Compilation message
savez.cpp:58:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
58 | main() {
| ^~~~
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
14 ms |
15960 KB |
Output is correct |
2 |
Correct |
15 ms |
16036 KB |
Output is correct |
3 |
Correct |
16 ms |
15956 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
15 ms |
15960 KB |
Output is correct |
2 |
Correct |
14 ms |
16108 KB |
Output is correct |
3 |
Correct |
14 ms |
16220 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
22 ms |
16984 KB |
Output is correct |
2 |
Correct |
21 ms |
17108 KB |
Output is correct |
3 |
Correct |
23 ms |
17500 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
18 ms |
16216 KB |
Output is correct |
2 |
Correct |
29 ms |
17448 KB |
Output is correct |
3 |
Correct |
27 ms |
17408 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
31 ms |
18796 KB |
Output is correct |
2 |
Correct |
23 ms |
19032 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
33 ms |
20572 KB |
Output is correct |
2 |
Correct |
27 ms |
21332 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
45 ms |
21328 KB |
Output is correct |
2 |
Correct |
35 ms |
23108 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
45 ms |
23124 KB |
Output is correct |
2 |
Correct |
49 ms |
26048 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
66 ms |
36948 KB |
Output is correct |
2 |
Correct |
59 ms |
42972 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
87 ms |
50444 KB |
Output is correct |
2 |
Correct |
80 ms |
60524 KB |
Output is correct |
3 |
Runtime error |
87 ms |
65536 KB |
Execution killed with signal 9 |
4 |
Halted |
0 ms |
0 KB |
- |