Submission #217865

#	Time	Username	Problem	Language	Result	Execution time	Memory
217865		aloo123	Palindromic Partitions (CEOI17_palindromic)	C++14	100 / 100	57 ms	11708 KiB

palindromic

#include <bits/stdc++.h>
#define ll long long
#define ld long double
#define mp make_pair
#define pb push_back
#define vll vector<ll>
#define endl "\n"
#define pll pair<ll,ll>
#define all(x) (x).begin() , (x).end()
#define f first
#define s second
using namespace std;
 
const ll N =(2e5+5);
const ll MOD = 998244353;
const ll INF = 1e16;
const ll LOG = 29;

long long binpow(long long a, long long b) {
     a %= MOD;
    long long res = 1;
    while (b > 0) {
        if (b & 1)
            res = (res * a)%MOD ;
        a = (a * a)%MOD ;
        b >>= 1;
    }
    res%=MOD;
    return res;
}
ll pp[1000005];

void solve(){
    string s;
    cin>>s;
    ll n = (ll)s.size();
    //cout<<n<<endl;
    ll l= 0,r= n -1;
    ll a=0;
    ll b=0;
    ll ans = 0;
    ll x=-1,y=n;
    ll lol = 0,gg=n-1;

    while(l < r){
        a = (a * LOG + (s[l]-'a'+1))%MOD; // 4
        b = ( b + pp[gg-r] * (s[r] - 'a' + 1))%MOD;//  
       // cout<<l<<" "<<r<<" --> " << a<< " "<<b<<endl;
        if(b == a){
            ans += 2;
            a=0;
            b=0;
            x = l,y =r;
            lol = l-1,gg = r-1;
            
        }

        l++,r--;
    }
    if((x+1)<=(y-1))
    ans++;
    cout<<ans<<endl;
}

int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(NULL);
    pp[0] = 1;
    for(int i =1;i<=1000000;i++)pp[i] = (pp[i-1] * LOG)%MOD;
    ll t;cin>>t;

    

    while(t--){
        solve();
    }



    return 0;     
    
        
}

Compilation message (stderr)

palindromic.cpp: In function 'void solve()':
palindromic.cpp:43:8: warning: variable 'lol' set but not used [-Wunused-but-set-variable]
     ll lol = 0,gg=n-1;
        ^~~

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