oj.uz

Submission #482952

# Submission time Handle Problem Language Result Execution time Memory
482952 2021-10-27T03:52:22 Z RGBB Palindromes (APIO14_palindrome) C++14
100 / 100
 523 ms 42108 KB 
#include <iostream>
#include <bits/stdc++.h>
using namespace std;
const int MAX=3*1e5;
int n;
string inp;
vector<int>sa;
long long outp;
int IS(int a,vector<int>&arr,vector<int>&s,vector<bool>&sl,vector<int>&lms){
    int i;
    vector<int>num(a),num2(a+1);
    for(i=0;i<s.size();i++){
        num[s[i]]++;
        num2[s[i]+1]++;
    }
    for(i=1;i<a;i++){
        num[i]+=num[i-1];
        num2[i]+=num2[i-1];
    }
    fill(arr.begin(),arr.end(),-1);
    for(i=lms.size()-1;i>=0;i--)arr[--num[s[lms[i]]]]=lms[i];
    for(i=0;i<s.size();i++)if(arr[i]>0&&!sl[arr[i]-1])arr[num2[s[arr[i]-1]]++]=arr[i]-1;
    for(i=0;i<lms.size();i++)num[s[lms[i]]]++;
    for(i=s.size()-1;i>=0;i--)if((arr[i]>0)&&sl[arr[i]-1])arr[--num[s[arr[i]-1]]]=arr[i]-1;
    return 0;
}
vector<int>SAIS(int a,vector<int>&s){
    int i;
    vector<int>arr(s.size()),lms,lms2,s2;
    vector<bool>sl(s.size());
    sl[s.size()-1]=1;
    for(i=s.size()-2;i>=0;i--){
        sl[i]=(s[i]<s[i+1])||((s[i]==s[i+1])&&sl[i+1]);
        if(!sl[i]&&sl[i+1])lms.push_back(i+1);
    }
    reverse(lms.begin(),lms.end());
    IS(a,arr,s,sl,lms);
    lms2.reserve(lms.size()),s2.reserve(lms.size());
    for(i=0;i<s.size();i++)if(arr[i]>0&&sl[arr[i]]&&!sl[arr[i]-1])lms2.push_back(arr[i]);
    int c=0;
    arr[s.size()-1]=c;
    for(i=1;i<lms2.size();i++){
        int x=lms2[i-1];
        int y=lms2[i];
        if(s[x]<s[y])c++;
        else{
            while(true){
                x++;
                y++;
                if(s[x]<s[y]){
                    c++;
                    break;
                }
                else if((sl[x]&&!sl[x-1])||(sl[y]&&!sl[y-1]))break;
            }
        }
        arr[lms2[i]]=c;
    }
    if(c+1<lms2.size()){
        for(i=0;i<lms.size();i++)s2.push_back(arr[lms[i]]);
        vector<int>arr2=SAIS(c+1,s2);
        for(i=0;i<lms.size();i++)lms2[i]=lms[arr2[i]];
    }
    IS(a,arr,s,sl,lms2);
    return arr;
}
vector<int>suffixArray(string&s){
    vector<int>s2(s.begin(),s.end());
    s2.push_back(0);
    s2=SAIS(256,s2);
    s2.erase(s2.begin());
    return s2;
}
vector<int>d1;
void oddManacher(){
    d1=vector<int>(n);
    for(int i=0,l=0,r=-1;i<n;i++){
        int k=(i>r)?1:min(d1[l+r-i],r-i+1);
        while(0<=i-k&&i+k<n&&inp[i-k]==inp[i+k])k++;
        d1[i]=k--;
        if(i+k>r){
            l=i-k;
            r=i+k;
        }
    }
}
vector<int>d2;
void evenManacher(){
    d2=vector<int>(n);
    for(int i=0,l=0,r=-1;i<n;i++){
        int k=(i>r)?0:min(d2[l+r-i+1],r-i+1);
        while(0<=i-k-1&&i+k<n&&inp[i-k-1]==inp[i+k])k++;
        d2[i]=k--;
        if(i+k>r){
            l=i-k-1;
            r=i+k;
        }
    }
}
int lzy[1<<20][2];
void delazy(int t,int a,int b,int c){
    if(a==b||lzy[c][t]==-1)return;
    lzy[2*c+1][t]=lzy[c][t];
    lzy[2*c+2][t]=lzy[c][t];
    lzy[c][t]=-1;
}
int querySeg(int t,int a,int b,int p,int c){
    if(a>p||b<p)return -1;
    delazy(t,a,b,c);
    if(a==b)return lzy[c][t];
    return max(querySeg(t,a,(a+b)/2,p,2*c+1),querySeg(t,(a+b)/2+1,b,p,2*c+2));
}
void updateSeg(int t,int a,int b,int be,int en,int c,int v){
    if(a>en||b<be)return;
    delazy(t,a,b,c);
    if(a>=be&&b<=en){
        lzy[c][t]=v;
        return;
    }
    updateSeg(t,a,(a+b)/2,be,en,2*c+1,v);
    updateSeg(t,(a+b)/2+1,b,be,en,2*c+2,v);
}
int bit[MAX+1];
int queryBit(int be,int en){
    int ret=0;
    for(en++;en>0;en-=en&-en)ret+=bit[en];
    for(;be>0;be-=be&-be)ret-=bit[be];
    return ret;
}
void updateBit(int p,int v){
    for(p++;p<=n;p+=p&-p)bit[p]+=v;
}
set<int>cnt[MAX];
void deleteRange(int be,int en,int p){
    while(cnt[p].lower_bound(be)!=cnt[p].end()){
        int cur=*cnt[p].lower_bound(be);
        if(cur>en)break;
        updateBit(cur,-1);
        cnt[p].erase(cnt[p].find(cur));
    }
}
void solve(int pty,vector<int>&d){
    memset(lzy,-1,sizeof(lzy));
    memset(bit,0,sizeof(bit));
    for(int i=0;i<n;i++)if(d[sa[i]]!=0)updateBit(i,1);
    for(int i=0;i<n;i++)cnt[i].clear();
    for(int i=0;i<n;i++)cnt[d[sa[i]]].insert(i);
    for(int i=0;i<n;i++){
        int cap=querySeg(0,0,n-1,i,0);
        int l=i;
        int r=querySeg(1,0,n-1,i,0);
        if(r==-1)r=n-1;
        int m=(l+r)/2;
        for(int j=cap+1;j<d[sa[i]];j++){
            while(r-l>1){
                if(inp[sa[i]+j]==(sa[m]+j<n?inp[sa[m]+j]:'$'))l=m;
                else r=m;
                m=(l+r)/2;
            }
            if(inp[sa[i]+j]==(sa[r]+j<n?inp[sa[r]+j]:'$'))m=r;
            else m=l;
            outp=max(outp,(long long)(2*j-pty+2)*queryBit(i,m));
            deleteRange(i,m,j+1);
            updateSeg(0,0,n-1,i,m,0,j);
            updateSeg(1,0,n-1,i,m,0,m);
            r=m;
            l=i;
        }
    }
}
int main(){
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cin>>inp;
    n=inp.length();
    sa=suffixArray(inp);
    oddManacher();
    evenManacher();
    solve(1,d1);
    solve(0,d2);
    cout<<outp<<"\n";
}

Compilation message

palindrome.cpp: In function 'int IS(int, std::vector<int>&, std::vector<int>&, std::vector<bool>&, std::vector<int>&)':
palindrome.cpp:12:14: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   12 |     for(i=0;i<s.size();i++){
      |             ~^~~~~~~~~
palindrome.cpp:22:14: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   22 |     for(i=0;i<s.size();i++)if(arr[i]>0&&!sl[arr[i]-1])arr[num2[s[arr[i]-1]]++]=arr[i]-1;
      |             ~^~~~~~~~~
palindrome.cpp:23:14: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   23 |     for(i=0;i<lms.size();i++)num[s[lms[i]]]++;
      |             ~^~~~~~~~~~~
palindrome.cpp: In function 'std::vector<int> SAIS(int, std::vector<int>&)':
palindrome.cpp:39:14: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   39 |     for(i=0;i<s.size();i++)if(arr[i]>0&&sl[arr[i]]&&!sl[arr[i]-1])lms2.push_back(arr[i]);
      |             ~^~~~~~~~~
palindrome.cpp:42:14: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   42 |     for(i=1;i<lms2.size();i++){
      |             ~^~~~~~~~~~~~
palindrome.cpp:59:11: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   59 |     if(c+1<lms2.size()){
      |        ~~~^~~~~~~~~~~~
palindrome.cpp:60:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   60 |         for(i=0;i<lms.size();i++)s2.push_back(arr[lms[i]]);
      |                 ~^~~~~~~~~~~
palindrome.cpp:62:18: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   62 |         for(i=0;i<lms.size();i++)lms2[i]=lms[arr2[i]];
      |                 ~^~~~~~~~~~~

Subtask #1
8.0 / 8.0

# Verdict Execution time Memory Grader output
1 Correct 11 ms 23756 KB Output is correct
2 Correct 11 ms 23756 KB Output is correct
3 Correct 11 ms 23792 KB Output is correct
4 Correct 12 ms 23752 KB Output is correct
5 Correct 13 ms 23752 KB Output is correct
6 Correct 11 ms 23756 KB Output is correct
7 Correct 11 ms 23884 KB Output is correct
8 Correct 11 ms 23756 KB Output is correct
9 Correct 12 ms 23776 KB Output is correct
10 Correct 11 ms 23756 KB Output is correct
11 Correct 11 ms 23756 KB Output is correct
12 Correct 11 ms 23792 KB Output is correct
13 Correct 11 ms 23756 KB Output is correct
14 Correct 11 ms 23756 KB Output is correct
15 Correct 11 ms 23756 KB Output is correct
16 Correct 11 ms 23756 KB Output is correct
17 Correct 11 ms 23756 KB Output is correct
18 Correct 11 ms 23756 KB Output is correct
19 Correct 11 ms 23752 KB Output is correct
20 Correct 11 ms 23756 KB Output is correct
21 Correct 11 ms 23796 KB Output is correct
22 Correct 11 ms 23796 KB Output is correct
23 Correct 11 ms 23756 KB Output is correct
24 Correct 11 ms 23756 KB Output is correct
25 Correct 11 ms 23756 KB Output is correct
26 Correct 11 ms 23756 KB Output is correct
27 Correct 11 ms 23756 KB Output is correct
28 Correct 11 ms 23720 KB Output is correct
29 Correct 11 ms 23756 KB Output is correct
30 Correct 11 ms 23704 KB Output is correct
31 Correct 11 ms 23756 KB Output is correct
32 Correct 11 ms 23748 KB Output is correct

Subtask #2
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 11 ms 23752 KB Output is correct
2 Correct 12 ms 23756 KB Output is correct
3 Correct 12 ms 23756 KB Output is correct
4 Correct 12 ms 23756 KB Output is correct
5 Correct 12 ms 23848 KB Output is correct
6 Correct 12 ms 23756 KB Output is correct
7 Correct 12 ms 23848 KB Output is correct
8 Correct 12 ms 23852 KB Output is correct
9 Correct 14 ms 23752 KB Output is correct
10 Correct 12 ms 23756 KB Output is correct
11 Correct 11 ms 23884 KB Output is correct
12 Correct 12 ms 23848 KB Output is correct

Subtask #3
24.0 / 24.0

# Verdict Execution time Memory Grader output
1 Correct 21 ms 24396 KB Output is correct
2 Correct 23 ms 24352 KB Output is correct
3 Correct 21 ms 24400 KB Output is correct
4 Correct 22 ms 24400 KB Output is correct
5 Correct 22 ms 24324 KB Output is correct
6 Correct 22 ms 24396 KB Output is correct
7 Correct 23 ms 24400 KB Output is correct
8 Correct 20 ms 24268 KB Output is correct
9 Correct 20 ms 24348 KB Output is correct
10 Correct 22 ms 24396 KB Output is correct

Subtask #4
26.0 / 26.0

# Verdict Execution time Memory Grader output
1 Correct 137 ms 29796 KB Output is correct
2 Correct 152 ms 29840 KB Output is correct
3 Correct 130 ms 29840 KB Output is correct
4 Correct 158 ms 29844 KB Output is correct
5 Correct 153 ms 29952 KB Output is correct
6 Correct 138 ms 29848 KB Output is correct
7 Correct 137 ms 29756 KB Output is correct
8 Correct 117 ms 29812 KB Output is correct
9 Correct 124 ms 29864 KB Output is correct
10 Correct 138 ms 29860 KB Output is correct

Subtask #5
27.0 / 27.0

# Verdict Execution time Memory Grader output
1 Correct 413 ms 41880 KB Output is correct
2 Correct 484 ms 41988 KB Output is correct
3 Correct 388 ms 41964 KB Output is correct
4 Correct 449 ms 41892 KB Output is correct
5 Correct 471 ms 41960 KB Output is correct
6 Correct 444 ms 41892 KB Output is correct
7 Correct 446 ms 41880 KB Output is correct
8 Correct 363 ms 41920 KB Output is correct
9 Correct 364 ms 41992 KB Output is correct
10 Correct 438 ms 41892 KB Output is correct
11 Correct 523 ms 42108 KB Output is correct
12 Correct 369 ms 41876 KB Output is correct