結果

問題 No.430 文字列検索
コンテスト
ユーザー Manuel1024
提出日時 2023-01-10 04:23:43
言語 C++14
(gcc 13.3.0 + boost 1.87.0)
結果
AC  
実行時間 1,136 ms / 2,000 ms
コード長 4,606 bytes
コンパイル時間 911 ms
コンパイル使用メモリ 101,504 KB
実行使用メモリ 6,400 KB
最終ジャッジ日時 2024-11-10 01:04:27
合計ジャッジ時間 12,839 ms
ジャッジサーバーID
（参考情報） 		judge5 / judge2
このコードへのチャレンジ
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ファイルパターン 結果
sample AC * 4
other AC * 14
権限があれば一括ダウンロードができます

ソースコード

diff # 

#include <iostream>
#include <vector>
#include <string>
#include <algorithm>
#include <random>
#include <chrono>
#include <cassert>
using namespace std;
using ll = long long;

struct RollingHash{
    static constexpr ll MOD = (1LL << 61)-1;

    const ll b1;
    const vector<ll> hs;
    const vector<ll> rev;
    RollingHash(const string &s): b1(rnd()), hs(make_hash(s)), rev(make_revlist(s.size())){
        // cerr << Mul(2, 2) << " " << Mul(18695992641856, 18695992641856) << endl;
        // cerr << Mul(1, 1) << endl;
    }
    RollingHash(const string &s, ll b0): b1(b0), hs(make_hash(s)), rev(make_revlist(s.size())){
        // cerr << Mul(3, 2) << " " << Mul(18695992641856, 18695992641856) <<
        // " " << mpow(172, MOD-2) << " " << mpow(172, 17) << endl;
        // cerr << endl;
    }

    // hash1(s[l, r)), hash2(s[l, r))
    ll get(int l, int r){
        return Mul(calcMod(MOD+hs[r]-hs[l]), rev[l]);//(hs[r]-hs[l]+MOD)%MOD*rev[l]%MOD
    }
private:
static constexpr ll MASK31 = (1LL << 31)-1;
static constexpr ll MASK30 = (1LL << 30)-1;
static constexpr ll MASK61 = (1LL << 61)-1;
    // a*b mod 2^61-1
    ll Mul(const ll a, const ll b){
        assert(MASK31 > 0);
        // cerr << a << " " << b << endl;
        ll au = a >> 31;
        ll ad = a & MASK31;
        ll bu = b >> 31;
        ll bd = b & MASK31;
        ll mid = ad*bu + au*bd;
        ll midu = mid >> 30;
        ll midd = mid & MASK30;
        /*
        cerr << a << " " << b << endl;
        cerr << au << " " << ad << " " << bu << " " << bd << " | " << mid << " " << midu << " " << midd << endl;
        cerr << (midd << 31) << endl;
        cerr << calcMod(au*bu*2 + midu + (midd << 31) + ad*bd) << endl;
        assert(false);
        */
        /*
        if(calcMod(au*bu*2 + midu + (midd << 31) + ad*bd) == 0 && a != 0 && b != 0){
            cerr << a << " * " << b << " = " << calcMod(au*bu*2 + midu + (midd << 31) + ad*bd) 
            << " (" << a*b << ")" << endl;
            cerr << (1LL & MASK31) << " " << MASK31 << " " << (1LL << 31) << endl;
            cerr << (a >> 31) << " " << (a & MASK31) << " " << (b >> 31) << " " << (b & MASK31) << endl;
            cerr << au << " " << ad << " " << bu << " " << bd << " | " << mid << " " << midu << " " << midd << endl;
        }
        */
        return calcMod(au*bu*2 + midu + (midd << 31) + ad*bd);
    }

    // x mod 2^61-1
    ll calcMod(ll x){
        ll xu = x >> 61;
        ll xd = x & MASK61;
        ll res = xu+xd;
        if(res >= MOD) res -= MOD;
        // assert(0 <= res && res < MOD);
        return res;
    }

    vector<ll> make_hash(const string &s){
        vector<ll> hs(s.size()+1);
        hs[0] = 0;
        ll bm = 1;
        for(int i = 0; i < s.size(); i++){
            hs[i+1] = calcMod(hs[i]+Mul(bm, s[i]));
            bm = Mul(bm, b1);
        }
        return hs;
    }

    // 逆元の前計算
    vector<ll> make_revlist(int n){
        vector<ll> rev(n);
        ll bm = 1;
        // cerr << b1 << " " << bm << " : ";
        for(int i = 0; i < n; i++){
            rev[i] = mpow(bm, MOD-2);
            // cerr << bm << " " << rev[i] << " ";
            bm = Mul(bm, b1);
        }
        // cerr << endl;
        return rev;
    }
    ll rnd(){
        mt19937_64 mt{1ULL * chrono::steady_clock::now().time_since_epoch().count()};
        return mt()%(MOD-2)+2;
    }
    ll mpow(ll a, ll x){
        // assert(0 < a && a < MOD);
        // cerr << "ok ";
        ll res = 1;
        for(; x > 0; x >>= 1){
            assert(0 <= a && a < MOD);
            assert(0 <= res && res < MOD);
            if(x & 1){
                res = Mul(res, a);
                // res *= a;
                // res %= MOD;
            }
            a = Mul(a, a);
            // a *= a;
            // a %= MOD;
            // cerr << res << " " << a << " ";
        }
        // cerr << endl;
        return res;
    }
};

int main(){
    string s; cin >> s;
    int m; cin >> m;
    vector<string> c(m);
    for(auto &it: c) cin >> it;

    RollingHash hs(s);
    vector<RollingHash> hc;
    for(auto &it: c) hc.emplace_back(it, hs.b1);

    // for(int i = 0; i < s.size(); i++) cerr << hs.rev[i] << " ";

    ll ans = 0;
    for(int i = 0; i < m; i++){
        // cerr << hc[i].get(0, c[i].size()) << " : ";
        for(int j = 0; j+c[i].size() <= s.size(); j++){
            if(hs.get(j, j+c[i].size()) == hc[i].get(0, c[i].size())){
                // cerr << hs.get(j, j+c[i].size()) << " ";
                ans++;
            }
        }
        // cerr << endl;
    }
    cout << ans << endl;
    return 0;
}
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