#include <bits/stdc++.h>
#define nl "\n"
#define no "NO"
#define yes "YES"
#define fi first
#define se second
#define vec vector
#define task "main"
#define _mp make_pair
#define ii pair<int, int>
#define sz(x) (int)x.size()
#define all(x) x.begin(), x.end()
#define evoid(val) return void(std::cout << val)
#define FOR(i, a, b) for(int i = (a); i <= (b); ++i)
#define FOD(i, b, a) for(int i = (b); i >= (a); --i)
#define unq(x) sort(all(x)); x.resize(unique(all(x)) - x.begin())
using namespace std;
template<typename U, typename V> bool maxi(U &a, V b) {
if (a < b) { a = b; return 1; } return 0;
}
template<typename U, typename V> bool mini(U &a, V b) {
if (a > b) { a = b; return 1; } return 0;
}
const int N = (int)2e5 + 9;
const int mod = (int)1e9 + 7;
void prepare(); void main_code();
int main() {
ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
if (fopen(task".inp", "r")) {
freopen(task".inp", "r", stdin);
freopen(task".out", "w", stdout);
}
const bool MULTITEST = 0; prepare();
int num_test = 1; if (MULTITEST) cin >> num_test;
while (num_test--) { main_code(); }
}
void prepare() {};
struct trie {
int cnt = 0;
trie *child[26];
};
trie *new_node() {
trie *n = new trie;
FOR(i, 0, 25) n -> child[i] = NULL;
return n;
}
int ins(trie* &r, char c) {
if (r->child[c-'a']==NULL)
r->child[c-'a']=new_node();
r=r->child[c-'a'];
++r->cnt;
return r->cnt;
}
void main_code() {
trie *odd_root = new_node();
trie *even_root = new_node();
string s; cin >> s;
int n = sz(s);
int ans = 0;
for(int i = 0; i < n; ++i) {
trie *r = odd_root;
for(int j = 0; j < min(i+1, n-i); ++j) {
if (s[i-j] != s[i+j]) break ;
int p = ins(r, s[i-j]);
ans = max(ans, (2 * j + 1) * p);
}
r = even_root;
for(int j = 0; j < min(i+1, n-i-1); ++j) {
if (s[i-j] != s[i+j+1]) break ;
int p = ins(r, s[i-j]);
ans = max(ans, 2 * (j + 1) * p);
}
}
cout << ans;
}
/* Let the river flows naturally */
Compilation message
palindrome.cpp: In function 'int main()':
palindrome.cpp:36:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
36 | freopen(task".inp", "r", stdin);
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
palindrome.cpp:37:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
37 | freopen(task".out", "w", stdout);
| ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 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 |
404 KB |
Output is correct |
8 |
Correct |
0 ms |
348 KB |
Output is correct |
9 |
Correct |
0 ms |
348 KB |
Output is correct |
10 |
Correct |
0 ms |
348 KB |
Output is correct |
11 |
Correct |
0 ms |
348 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 |
360 KB |
Output is correct |
16 |
Correct |
0 ms |
348 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 |
348 KB |
Output is correct |
21 |
Correct |
0 ms |
348 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 |
0 ms |
344 KB |
Output is correct |
26 |
Correct |
0 ms |
348 KB |
Output is correct |
27 |
Correct |
0 ms |
348 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 |
348 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
604 KB |
Output is correct |
2 |
Correct |
1 ms |
604 KB |
Output is correct |
3 |
Correct |
2 ms |
604 KB |
Output is correct |
4 |
Correct |
0 ms |
604 KB |
Output is correct |
5 |
Correct |
3 ms |
636 KB |
Output is correct |
6 |
Correct |
3 ms |
676 KB |
Output is correct |
7 |
Correct |
0 ms |
604 KB |
Output is correct |
8 |
Correct |
1 ms |
604 KB |
Output is correct |
9 |
Correct |
0 ms |
456 KB |
Output is correct |
10 |
Correct |
0 ms |
348 KB |
Output is correct |
11 |
Correct |
0 ms |
344 KB |
Output is correct |
12 |
Correct |
0 ms |
604 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
233 ms |
2644 KB |
Output is correct |
2 |
Correct |
107 ms |
2640 KB |
Output is correct |
3 |
Correct |
111 ms |
2640 KB |
Output is correct |
4 |
Correct |
107 ms |
2656 KB |
Output is correct |
5 |
Correct |
1 ms |
2652 KB |
Output is correct |
6 |
Correct |
4 ms |
2652 KB |
Output is correct |
7 |
Correct |
24 ms |
2464 KB |
Output is correct |
8 |
Correct |
0 ms |
348 KB |
Output is correct |
9 |
Correct |
0 ms |
348 KB |
Output is correct |
10 |
Correct |
1 ms |
1884 KB |
Output is correct |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Execution timed out |
1069 ms |
6996 KB |
Time limit exceeded |
2 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Execution timed out |
1062 ms |
7216 KB |
Time limit exceeded |
2 |
Halted |
0 ms |
0 KB |
- |