Submission #771487

#	Time	Username	Problem	Language	Result	Execution time	Memory
771487		Blistering_Barnacles	Necklace (Subtask 1-3) (BOI19_necklace1)	C++11	85 / 85	263 ms	225644 KiB

necklace

//Billions of bilious blue blistering barnacles in a thundering typhoon!
#ifndef LOCAL
#pragma GCC optimize("Ofast,fast-math,unroll-loops")
#pragma GCC target("avx2,fma")
#endif
#include<bits/stdc++.h>
#define fast ios::sync_with_stdio(0) , cin.tie(0)
#define F first
#define S second
#define pb push_back
#define vll vector< ll >
#define vi vector< int >
#define pll pair< ll , ll >
#define pi pair< int , int >
#define all(s) s.begin() , s.end()
#define sz(s) s.size()
#define str string
#define md ((s + e) / 2)
#define mid ((l + r) / 2)
#define msdp(dp) memset(dp , -1 , sizeof dp)
#define mscl(dp) memset(dp , 0 , sizeof dp)
#define C continue
#define R return
#define B break
#define lx node * 2
#define rx node * 2 + 1
#define br(dosomething) {dosomething; break;}
#define co(dosomething) {dosomething ; continue;}
using namespace std;
typedef long long ll;
ll q, a[555555] , b[555555] , dp[555555] , k, l, m, n, o, p;
map < ll , ll > mp ;
vll adj[555555];
const ll mod = 1e9+7;
ll Lss[3005][3005] , Lsp[3005][3005] , Lps[3005][3005] ;
str s , t ; 
void solve(){
    cin >> s >> t ; 
    n = sz(s) , m = sz(t) ; 
    reverse(all(t)) ; 
    str op = t ; 
    s = ' ' + s , t = ' ' + t ; 
    for(ll i = 1 ; i <= n ; i++){
        for(ll j = 1 ; j <= m ; j++){
            Lss[i][j] = (s[i] == t[j] ? 1 + Lss[i - 1][j - 1] : 0) ;
        }
    }
    for(ll i = 1 ; i <= n ; i++){
        for(ll j = 1 ; j <= m ; j++){
            if(!Lss[i][j])C ; 
            Lsp[i][j - Lss[i][j] + 1] = max(Lsp[i][j - Lss[i][j] + 1] , Lss[i][j]) ; 
        }
    }
    for(ll i = 1 ; i <= n ; i++){
        for(ll j = 1 ; j <= m ; j++){
            if(!Lss[i][j])C ;
            Lps[i - Lss[i][j] + 1][j] = max(Lps[i - Lss[i][j] + 1][j] , Lss[i][j]) ; 
        }
    }
    pair < ll , pll > ans = {0 , {0 , 0}} ; 
    //for(ll i = 1 ; i <= n ; i++){
        //for(ll j = 1 ; j <= m ; j++){
            //Lsp[i][j] = max(Lsp[i][j] , Lsp[i][j - 1] - 1) ; 
            //Lps[i][j] = max(Lps[i][j] , Lps[i - 1][j] - 1) ;
        //}
    //}
    for(ll i = 1 ; i <= n ; i++){
        for(ll j = 1 ; j <= m ; j++){
            ans = max(ans , {Lsp[i][j] + Lps[i + 1][j - 1] , {i - Lsp[i][j] , m - j - Lsp[i][j] + 1}}) ;
        }
    }
    reverse(all(op)) ; 
    t = op ; 
    t = ' ' + t ; 
    mscl(Lss) , mscl(Lsp) , mscl(Lps) ; 
    for(ll i = 1 ; i <= n ; i++){
        for(ll j = 1 ; j <= m ; j++){
            Lss[i][j] = (s[i] == t[j] ? 1 + Lss[i - 1][j - 1] : 0) ;
        }
    }
    for(ll i = 1 ; i <= n ; i++){
        for(ll j = 1 ; j <= m ; j++){
            if(!Lss[i][j])C ; 
            Lsp[i][j - Lss[i][j] + 1] = max(Lsp[i][j - Lss[i][j] + 1] , Lss[i][j]) ; 
        }
    }
    for(ll i = 1 ; i <= n ; i++){
        for(ll j = 1 ; j <= m ; j++){
            if(!Lss[i][j])C ;
            Lps[i - Lss[i][j] + 1][j] = max(Lps[i - Lss[i][j] + 1][j] , Lss[i][j]) ; 
        }
    }
    //for(ll i = 1 ; i <= n ; i++){
        //for(ll j = 1 ; j <= m ; j++){
            //Lsp[i][j] = max(Lsp[i][j] , Lsp[i][j - 1] - 1) ; 
            //Lps[i][j] = max(Lps[i][j] , Lps[i - 1][j] - 1) ;
        //}
    //}
    for(ll i = 1 ; i <= n ; i++){
        for(ll j = 1 ; j <= m ; j++){
            ans = max(ans , {Lsp[i][j] + Lps[i + 1][j - 1] , {i - Lsp[i][j] , j - Lps[i + 1][j - 1] - 1}}) ;
        }
    }
    cout << ans.F << endl << ans.S.F << " "  << ans.S.S << endl ; 
}
int main(){
    fast ;
    q = 1 ;
    //cin >> q ;
    while(q--){
        solve() ;
    }
}

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