Submission #448647

#	Time	Username	Problem	Language	Result	Execution time	Memory
448647		Khizri	Palindromic Partitions (CEOI17_palindromic)	C++17	100 / 100	113 ms	20608 KiB

palindromic

#include <bits/stdc++.h>
using namespace std;
//------------------------------DEFINE------------------------------
//******************************************************************
#define IOS ios_base::sync_with_stdio(false); cin.tie(0),cout.tie(0)
#define ll long long
#define pb push_back		 
#define F first																 
#define S second 															 
#define INF 1e18
#define all(v) (v).begin(),(v).end()
#define rall(v) (v).rbegin(),(v).rend()
#define pii pair<int,int>
#define pll pair<ll,ll>
#define OK cout<<"Ok"<<endl;
#define MOD (ll)(1712429437)
#define endl "\n"
//******************************************************************
//----------------------------FUNCTION------------------------------
//******************************************************************
ll gcd(ll a,ll b){
	if(a>b) swap(a,b);
	if(a==0) return a+b;
	return gcd(b%a,a);
}
ll lcm(ll a,ll b){
	return a/gcd(a,b)*b;
}
bool is_prime(ll n){
	ll k=sqrt(n);
	if(n==2) return true;
	if(n<2||n%2==0||k*k==n) return false;
	for(int i=3;i<=k;i+=2){
		if(n%i==0){
			return false;
		}
	}
	return true;
}
//*****************************************************************
//--------------------------MAIN-CODE------------------------------
const int mxn=1e6+5;
ll t=1,p[mxn];
map<char,ll>mp;
void f(){
	p[0]=1;
	for(int i=1;i<=1e6;i++){
		p[i]=(p[i-1]*26)%MOD;
	}
	ll k=0;
	for(char i='a';i<='z';i++){
		mp[i]=++k;
	}
}
void solve(){
	string s;
	cin>>s;
	ll x=0,y=0,l=0,r=s.size()-1,l1=0,r1=s.size()-1;
	ll ans=0;
	while(l<r){
		x=((x*26)%MOD+mp[s[l]])%MOD;
		y=((p[(r1-r)]*mp[s[r]])%MOD+y)%MOD;
		l++,r--;
		if(x==y){
			ans+=2;
			x=0,y=0;
			r1=r;
		}
	}
	if(l==r||x>0||y>0){
		ans++;
	}
	cout<<ans<<endl;
}
int main(){
	IOS;
	f();
	cin>>t;
	while(t--){
		solve();
	}
	return 0;
}

Compilation message (stderr)

palindromic.cpp: In function 'void solve()':
palindromic.cpp:58:30: warning: unused variable 'l1' [-Wunused-variable]
   58 |  ll x=0,y=0,l=0,r=s.size()-1,l1=0,r1=s.size()-1;
      |                              ^~

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