#include <bits/stdc++.h>
using namespace std;
#define X first
#define Y second
#define rep(i,a,b) for(int i=a;i<=b;i++)
#define IOS ios::sync_with_stdio(0);cin.tie(0);
#define de(x,y) cout<<#x<<" :"<<x<<y;
#define int long long
#define SZ(xx) ((int)xx.size())
#define lowbit(xx) (xx&(-xx))
#define pb push_back
typedef pair<int,int> pii;
const int maxn = 4e5+5;
int arr[maxn], ans = 0;
vector<int> vt, G[maxn];
double start;
bool check() {
vector<int> rvt = vt;
reverse(rvt.begin(), rvt.end());
for(int i=0; i<vt.size(); i++) {
if(vt[i]^rvt[i])
return 0;
}
return 1;
}
void dfs(int now,int fa) {
vt.push_back(arr[now]);
if(check())
ans = max(ans, SZ(vt));
for(int k:G[now])
if(k != fa)
dfs(k, now);
vt.pop_back();
if((clock()-start)/CLOCKS_PER_SEC>4.9) {
cout << ans << "\n";
exit(0);
}
}
void solve() {
string s;
cin >> s;
int ans = 1 , len = s.size();
for(int i=0;i<s.size()-1;i++) {
int tmp = 1;
for(int j=1;j<=s.size();j++) {
if(i-j < 0 || i+j >= len)
break;
if(s[i - j] != s[i + j])
break;
tmp += 2;
}
ans = max(ans , tmp);
if(s[i] == s[i+1]) {
tmp = 2;
for(int j=1;j<=s.size();j++) {
if(i-j < 0 || i+j+1 >= len)
break;
if(s[i - j] != s[i + j+1])
break;
tmp += 2;
}
}
ans = max(ans , tmp);
if(ans == len)
break;
}
cout << ans << "\n";
}
main() {
IOS
start = clock();
mt19937 mt_rand(time(0));
double start=clock();
int n;
cin >> n;
for(int i=1; i<=n; i++) {
char c;
cin >> c;
arr[i] = c - 'a';
}
for(int i=1; i<n; i++) {
int u, v;
cin >> u >> v;
G[u].push_back(v);
G[v].push_back(u);
}
for(int i=n; i>=1; i--) {
dfs(rand() % n + 1, 0);
}
cout << ans << "\n";
}
Compilation message
lampice.cpp: In function 'bool check()':
lampice.cpp:21:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
for(int i=0; i<vt.size(); i++) {
~^~~~~~~~~~
lampice.cpp: In function 'void solve()':
lampice.cpp:46:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
for(int i=0;i<s.size()-1;i++) {
~^~~~~~~~~~~
lampice.cpp:48:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
for(int j=1;j<=s.size();j++) {
~^~~~~~~~~~
lampice.cpp:58:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
for(int j=1;j<=s.size();j++) {
~^~~~~~~~~~
lampice.cpp: At global scope:
lampice.cpp:73:6: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
main() {
^
lampice.cpp: In function 'int main()':
lampice.cpp:78:9: warning: unused variable 'start' [-Wunused-variable]
double start=clock();
^~~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
74 ms |
9720 KB |
Output is correct |
| 2 |
Correct |
319 ms |
9720 KB |
Output is correct |
| 3 |
Incorrect |
1312 ms |
9976 KB |
Output isn't correct |
| 4 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Execution timed out |
5047 ms |
14184 KB |
Time limit exceeded |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Incorrect |
4914 ms |
12692 KB |
Output isn't correct |
| 2 |
Halted |
0 ms |
0 KB |
- |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
74 ms |
9720 KB |
Output is correct |
| 2 |
Correct |
319 ms |
9720 KB |
Output is correct |
| 3 |
Incorrect |
1312 ms |
9976 KB |
Output isn't correct |
| 4 |
Halted |
0 ms |
0 KB |
- |
