Submission #586292

#	Time	Username	Problem	Language	Result	Execution time	Memory
586292		lalala56	Palindromic Partitions (CEOI17_palindromic)	C++14	0 / 100	0 ms	340 KiB

palindromic

#include<bits/stdc++.h>
using namespace std;
#define ll long long
const ll mod=1e9+7,ba=9907;
const int N=1e6+9;
ll h[N],p[N];
int n,res;
string s;
ll hass(int l,int r){
    return (h[r]-h[l-1]*p[r-l+1]+mod*mod)%mod;
}
void giai(){
    cin>>s;
    n=s.length();
    s=' '+s;
    p[0]=1;
    for(int i=1;i<=n;i++)p[i]=(p[i-1]*ba)%mod;
    for(int i=1;i<=n;i++){
        h[i]=(h[i-1]*ba+int(s[i])-'a'+1)%mod;
    }
    res=1;
    int p=1,q=n;
    //cout<<n<<" "<<s<<" ";
    for(int i=1;i<=n/2;i++){
        if(hass(p,i)==hass(n-i+1,q)){
            //cout<<i<<endl;
            p=i+1;
            q=n-i;
            res+=2;
        }
    }
    cout<<res<<'\n';
}
int main(){
   // freopen("solve.inp","r",stdin);
   // freopen("solve.out","w",stdout);
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    int t;
    cin>>t;
    while(t--)giai();
}

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