Submission #209622

# Submission time Handle Problem Language Result Execution time Memory
209622 2020-03-14T22:19:34 Z thebes Necklace (Subtask 1-3) (BOI19_necklace1) C++14
45 / 85
1500 ms 376 KB
#pragma GCC optimize("Ofast")
#pragma GCC optimize("unroll-loops")
#pragma GCC target("sse,sse2,ssse3,sse3,sse4,popcnt,avx,mmx,abm,tune=native")
#include <bits/stdc++.h>
#define DEBUG 1
using namespace std;

namespace output{
    void __(short x){cout<<x;}
    void __(unsigned x){cout<<x;}
    void __(int x){cout<<x;}
    void __(long long x){cout<<x;}
    void __(unsigned long long x){cout<<x;}
    void __(double x){cout<<x;}
    void __(long double x){cout<<x;}
    void __(char x){cout<<x;}
    void __(const char*x){cout<<x;}
    void __(const string&x){cout<<x;}
    void __(bool x){cout<<(x?"true":"false");}
    template<class S,class T>
    void __(const pair<S,T>&x){__(DEBUG?"(":""),__(x.first),__(DEBUG?", ":" "),__(x.second),__(DEBUG?")":"");}
    template<class T>
    void __(const vector<T>&x){__(DEBUG?"{":"");bool _=0;for(const auto&v:x)__(_?DEBUG?", ":" ":""),__(v),_=1;__(DEBUG?"}":"");}
    template<class T>
    void __(const set<T>&x){__(DEBUG?"{":"");bool _=0;for(const auto&v:x)__(_?DEBUG?", ":" ":""),__(v),_=1;__(DEBUG?"}":"");}
    template<class T>
    void __(const multiset<T>&x){__(DEBUG?"{":"");bool _=0;for(const auto&v:x)__(_?DEBUG?", ":" ":""),__(v),_=1;__(DEBUG?"}":"");}
    template<class S,class T>
    void __(const map<S,T>&x){__(DEBUG?"{":"");bool _=0;for(const auto&v:x)__(_?DEBUG?", ":" ":""),__(v),_=1;__(DEBUG?"}":"");}
    void pr(){cout<<"\n";}
    template<class S,class... T>
    void pr(const S&a,const T&...b){__(a);if(sizeof...(b))__(' ');pr(b...);}
}

using namespace output;

typedef long long ll;
typedef long double ld;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;
typedef pair<int,char> pic;
typedef pair<double,double> pdd;
typedef pair<ld,ld> pld;
typedef vector<int> vi;
typedef vector<ll> vl;
typedef pair<int,vi> piv;

#define pb push_back
#define fox(i,x,y) for(int i=(x);i<=(y);i++)
#define foxr(i,x,y) for(int i=(y);i>=(x);i--)

const int MN = 3003;
string s, t;
int n, m, i, hsh[2][MN], pw[MN]={1}, pre[MN], suf[MN], st[MN], len[MN], lo, hi, lim1, lim2, ans, sw, fl, ree, k, sh, mid;
inline int gethsh(int id,int x,int y){return hsh[id][y]-hsh[id][x-1]*pw[y-x+1];}
pii sna; queue<pii> hm;

void solve(int init=0){
    for(int i=1;i<=m;i++)
        hsh[1][i]=hsh[1][i-1]*133+t[i-1]-'a'+1;
    k = min(m,lim2);
    for(int i=1;i<=n;i++){
        if(s[i-1]!=t[m-1]){
            suf[i]=0;
            continue;
        }
        //if(init||i==n){
            hi=min(i,k);
            lo=min(hi,max(0,suf[i+1]-1));
            while(lo<hi){
                mid = (lo+hi)/2;
                if(gethsh(0,i-mid,i)==gethsh(1,m-mid,m)) lo=mid+1;
                else hi=mid;
            }
            suf[i]=lo;
        /*}
        else{
            suf[i]=max(0,suf[i+1]-1);
        }*/
    }
    while(hm.size()) hm.pop();
    for(int i=n;i>=1;i--){
        if(suf[i]) hm.push({suf[i],i});
        while(hm.size()){
            if(hm.front().second-hm.front().first+1>i) hm.pop();
            else break;
        }
        if(hm.size()){
            st[i] = lim2-hm.front().first;
            len[i] = hm.front().second-i+1;
        }
        else len[i] = 0, st[i] = lim2;  
    }
    k = min(m,lim1);
    for(int i=n;i>=1;i--){
        if(s[i-1]!=t[0]){
            pre[i]=0;
            continue;
        }
        hi=min(n-i+1,k);
        lo=min(hi,max(pre[i-1]-1,0));
        while(lo<hi){
            mid = (lo+hi)/2;
            if(gethsh(0,i,i+mid)==gethsh(1,1,1+mid)) lo=mid+1;
            else hi=mid;
        }
        pre[i]=lo;
    }
    while(hm.size()) hm.pop();
    for(int i=1;i<=n;i++){
        if(pre[i]) hm.push({pre[i],i});
        while(hm.size()){
            if(hm.front().second+hm.front().first-1<i) hm.pop();
            else break;
        }
        if(hm.size()){
            len[i] = i-hm.front().second+1;
            if(len[i]+len[i+1]>ans){
                ans = len[i]+len[i+1];
                if(sw) sna = {n-(i+len[i+1]), st[i+1]};
                else sna = {hm.front().second-1, st[i+1]};
            }
        }
    }
}

int main(){
    cin >> s >> t;
    n = s.size(), m = t.size();
    for(i=1;i<MN;i++)
        pw[i]=133*pw[i-1];
    for(i=1;i<=n;i++)
        hsh[0][i]=hsh[0][i-1]*133+s[i-1]-'a'+1;
    lim1 = 0; lim2 = m;
    solve(1);
    for(i=1;i<=m;i++){
        lim1++; lim2--;
        char ch = t.back(); t.erase(t.end()-1);
        t.insert(t.begin(),ch);
        solve();
    }
    for(i=0;i<s.size()/2;i++)
        swap(s[i],s[s.size()-i-1]);
    for(i=1;i<=n;i++)
        hsh[0][i]=hsh[0][i-1]*133+s[i-1]-'a'+1;
    lim1 = 0; lim2 = m; sw = 1;
    solve(1);
    for(i=1;i<=m;i++){
        lim1++; lim2--;
        char ch = t.back(); t.erase(t.end()-1);
        t.insert(t.begin(),ch);
        solve();
    }
    printf("%d\n%d %d\n",ans,sna.first,sna.second);
    return 0;
}

Compilation message

necklace.cpp: In function 'int main()':
necklace.cpp:142:14: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(i=0;i<s.size()/2;i++)
             ~^~~~~~~~~~~
# Verdict Execution time Memory Grader output
1 Correct 6 ms 376 KB Output is correct
2 Correct 5 ms 376 KB Output is correct
3 Correct 6 ms 376 KB Output is correct
4 Correct 5 ms 376 KB Output is correct
5 Correct 5 ms 376 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 6 ms 376 KB Output is correct
2 Correct 5 ms 376 KB Output is correct
3 Correct 6 ms 376 KB Output is correct
4 Correct 5 ms 376 KB Output is correct
5 Correct 5 ms 376 KB Output is correct
6 Correct 27 ms 376 KB Output is correct
7 Correct 17 ms 376 KB Output is correct
8 Correct 29 ms 376 KB Output is correct
9 Correct 21 ms 376 KB Output is correct
10 Correct 9 ms 376 KB Output is correct
11 Correct 10 ms 376 KB Output is correct
12 Correct 22 ms 376 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 6 ms 376 KB Output is correct
2 Correct 5 ms 376 KB Output is correct
3 Correct 6 ms 376 KB Output is correct
4 Correct 5 ms 376 KB Output is correct
5 Correct 5 ms 376 KB Output is correct
6 Correct 27 ms 376 KB Output is correct
7 Correct 17 ms 376 KB Output is correct
8 Correct 29 ms 376 KB Output is correct
9 Correct 21 ms 376 KB Output is correct
10 Correct 9 ms 376 KB Output is correct
11 Correct 10 ms 376 KB Output is correct
12 Correct 22 ms 376 KB Output is correct
13 Execution timed out 1597 ms 376 KB Time limit exceeded
14 Halted 0 ms 0 KB -