oj.uz

Submission #933691

# Submission time Handle Problem Language Result Execution time Memory
933691 2024-02-26T05:36:43 Z guagua0407 Palindromes (APIO14_palindrome) C++17
47 / 100
 410 ms 28328 KB 
#pragma GCC optimize("O3")
#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define pii pair<int,int>
#define f first
#define s second
#define all(x) x.begin(),x.end()
#define _ ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);

int dx[4]={0,0,1,-1};
int dy[4]={1,-1,0,0};

void setIO(string s) {
    freopen((s + ".in").c_str(), "r", stdin);
    freopen((s + ".out").c_str(), "w", stdout);
}

const ll p=29;
const ll mod=1e9+7;
const int mxn=3e5+5;
ll powv[mxn];
ll hashr[mxn],hashl[mxn];
map<ll,int> mp;

void build(string str){
    int n=str.length();
    powv[0]=1;
    for(int i=1;i<=n;i++){
        powv[i]=/*(__int128)*/1ll*powv[i-1]*p%mod;
    }
    for(int i=1;i<n;i++){
        hashr[i]=(/*(__int128)*/1ll*hashr[i-1]*p%mod+(str[i]-'a'+1))%mod;
    }
    for(int i=n-1;i>=1;i--){
        hashl[i]=(/*(__int128)*/1ll*hashl[i+1]*p%mod+(str[i]-'a'+1))%mod;
    }
}

ll get1(int l,int r){
    ll ans=(hashl[l]-/*(__int128)*/1ll*hashl[r+1]*powv[r-l+1]%mod)%mod;
    if(ans<0) ans+=mod;
    return ans;
}

ll get2(int l,int r){
    ll ans=(hashr[r]-/*(__int128)*/1ll*hashr[l-1]*powv[r-l+1]%mod)%mod;
    if(ans<0) ans+=mod;
    return ans;
}

bool same(int l1,int r1,int l2,int r2){
    ll v1=get1(l1,r1);
    ll v2=get2(l2,r2);
    return v1==v2;
}

int main() {_
    string str;
    cin>>str;
    int n=(int)str.length();
    str="#"+str;
    build(str);
    priority_queue<pair<int,pair<int,int>>> pq;
    for(int i=1;i<=n;i++){
        {
            int l=0,r=min(i-1,n-i);
            while(l<r){
                int mid=(l+r+1)/2;
                if(same(i-mid,i-1,i+1,i+mid)){
                    l=mid;
                }
                else{
                    r=mid-1;
                }
            }
            ll val=get2(i-l,i+l);
            mp[val]++;
            if(mp[val]==1) pq.push({2*l+1,{i-l,i+l}});
        }
        {
            int l=0,r=min(i-1,n-i+1);
            while(l<r){
                int mid=(l+r+1)/2;
                if(same(i-mid,i-1,i,i+mid-1)){
                    l=mid;
                }
                else{
                    r=mid-1;
                }
            }
            if(l>0){
                ll val=get2(i-l,i+l-1);
                mp[val]++;
                if(mp[val]==1) pq.push({2*l,{i-l,i+l-1}});
            }
        }
    }
    ll ans=1;
    while(!pq.empty()){
        auto tmp=pq.top();
        pq.pop();
        int len=tmp.f;
        int l=tmp.s.f;
        int r=tmp.s.s;
        ll val=get2(l,r);
        int cnt=mp[val];
        ans=max(ans,1ll*cnt*len);
        l++;
        r--;
        if(l<=r){
            ll val2=get2(l,r);
            mp[val2]+=cnt;
            if(mp[val2]==cnt) pq.push({r-l+1,{l,r}});
        }
    }
    cout<<ans<<'\n';
    return 0;
}
//maybe its multiset not set
//yeeorz
//laborz

Compilation message

palindrome.cpp: In function 'void setIO(std::string)':
palindrome.cpp:15:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   15 |     freopen((s + ".in").c_str(), "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
palindrome.cpp:16:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   16 |     freopen((s + ".out").c_str(), "w", stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
8.0 / 8.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 2396 KB Output is correct
2 Correct 1 ms 2648 KB Output is correct
3 Correct 1 ms 2396 KB Output is correct
4 Correct 1 ms 2396 KB Output is correct
5 Correct 0 ms 2396 KB Output is correct
6 Correct 0 ms 2396 KB Output is correct
7 Correct 0 ms 2396 KB Output is correct
8 Correct 0 ms 2396 KB Output is correct
9 Correct 0 ms 2392 KB Output is correct
10 Correct 1 ms 2392 KB Output is correct
11 Correct 1 ms 2396 KB Output is correct
12 Correct 0 ms 2396 KB Output is correct
13 Correct 1 ms 2396 KB Output is correct
14 Correct 0 ms 2396 KB Output is correct
15 Correct 1 ms 2396 KB Output is correct
16 Correct 0 ms 2396 KB Output is correct
17 Correct 1 ms 2396 KB Output is correct
18 Correct 1 ms 2396 KB Output is correct
19 Correct 1 ms 2396 KB Output is correct
20 Correct 1 ms 2396 KB Output is correct
21 Correct 1 ms 2396 KB Output is correct
22 Correct 1 ms 2396 KB Output is correct
23 Correct 1 ms 2396 KB Output is correct
24 Correct 1 ms 2396 KB Output is correct
25 Correct 1 ms 2396 KB Output is correct
26 Correct 1 ms 2392 KB Output is correct
27 Correct 1 ms 2396 KB Output is correct
28 Correct 1 ms 2396 KB Output is correct
29 Correct 1 ms 2396 KB Output is correct
30 Correct 1 ms 2396 KB Output is correct
31 Correct 0 ms 2396 KB Output is correct
32 Correct 1 ms 2396 KB Output is correct

Subtask #2
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 1 ms 2396 KB Output is correct
2 Correct 1 ms 2396 KB Output is correct
3 Correct 1 ms 2612 KB Output is correct
4 Correct 1 ms 2552 KB Output is correct
5 Correct 1 ms 2396 KB Output is correct
6 Correct 1 ms 2396 KB Output is correct
7 Correct 1 ms 2396 KB Output is correct
8 Correct 1 ms 2396 KB Output is correct
9 Correct 1 ms 2396 KB Output is correct
10 Correct 1 ms 2396 KB Output is correct
11 Correct 1 ms 2396 KB Output is correct
12 Correct 1 ms 2396 KB Output is correct

Subtask #3
24.0 / 24.0

# Verdict Execution time Memory Grader output
1 Correct 9 ms 3420 KB Output is correct
2 Correct 9 ms 3164 KB Output is correct
3 Correct 10 ms 3420 KB Output is correct
4 Correct 13 ms 3420 KB Output is correct
5 Correct 6 ms 3212 KB Output is correct
6 Correct 7 ms 3164 KB Output is correct
7 Correct 9 ms 3416 KB Output is correct
8 Correct 3 ms 2804 KB Output is correct
9 Correct 3 ms 2652 KB Output is correct
10 Correct 5 ms 2908 KB Output is correct

Subtask #4
0 / 26.0

# Verdict Execution time Memory Grader output
1 Incorrect 115 ms 11456 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #5
0 / 27.0

# Verdict Execution time Memory Grader output
1 Incorrect 410 ms 28328 KB Output isn't correct
2 Halted 0 ms 0 KB -