Submission #939169

#	Time	Username	Problem	Language	Result	Execution time	Memory
939169		vjudge1	Palindromic Partitions (CEOI17_palindromic)	C++17	0 / 100	6 ms	8028 KiB

palindromic

#include <bits/stdc++.h>
#define int long long
#define ff first
#define ss second
#define pb push_back
#define all(x) x.begin(),x.end()
using namespace std;
const int N=1e6+5,mod=1e9+7,tt=13;
int pw[N];
signed main(){
    ios_base::sync_with_stdio();
    cin.tie(0);cout.tie(0);
    int t;
    cin>>t;
    pw[0]=1;
    for(int i=1;i<N;i++){
        pw[i]=pw[i-1]*tt;
        pw[i]%=mod;
    }
    while(t--){
        string s;
        cin>>s;
        s=" "+s;
        vector <int> h(s.size());
        for(int i=1;i<s.size();i++){
            h[i]=h[i-1]*tt+(s[i]-'a'+1);
            h[i]%=mod;
        }
        int st1=1,end2=s.size()-1;
        int end1=1,st2=s.size()-1;
        int h1=0,h2=0;
        int ans=0;
        while(end1<st2){
            h1=(h[end1]-h[st1-1]*pw[end1-st1+1])%mod;
            h2=(h[end2]-h[st2-1]*pw[end2-st2+1])%mod;
            if(h1==h2){
                end1++;
                st1=end1;
                st2--;
                end2=st2;
                ans+=2;
            }
            else{
                st2--;
                end1++;
            }
        }
        if(st1<=end2)ans++;
        cout<<ans<<"\n";
    }
    
}
/*

*/
           
 
           

Compilation message (stderr)

palindromic.cpp: In function 'int main()':
palindromic.cpp:25:22: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   25 |         for(int i=1;i<s.size();i++){
      |                     ~^~~~~~~~~

• Subtask 1: 0 / 15
• Subtask 2: 0 / 20
• Subtask 3: 0 / 25
• Subtask 4: 0 / 40