Cod sursa(job #3314064)

Utilizator Alex_at_gameIustin-Alexandru Frateanu Alex_at_game Data 8 octombrie 2025 10:28:17
Problema Potrivirea sirurilor Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 3.61 kb
/**
    Frățeanu Iustin-Alexandru
    397916YC
**/
#pragma GCC optimize("Ofast,no-stack-protector,unroll-loops,fast-math")
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
using namespace std;
using namespace __gnu_pbds;
using ll = long long;
using ull = unsigned long long;
using i128 = __int128_t;
using ui128 = __uint128_t;
using sint = short int;
using pii = pair<int, int>;
using pll = pair<ll, ll>;
using vpi = vector<pii>;
using vpl = vector<pll>;
template<typename T>
using vvector = vector<vector<T>>;
template<typename K, typename V>
using umap = unordered_map<K, V>;
template<typename T>
using uset = unordered_set<T>;
template<typename T>
using oset = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
template<typename A, typename B>
using vp = vector<pair<A, B>>;
#define FAST ios_base::sync_with_stdio(false); cin.tie(nullptr); cout.tie(nullptr);
#define all(v) begin(v), end(v)
#define rall(v) rbegin(v), rend(v)
#define al(v, st, dr) begin(v) + st, begin(v) + dr
#define ral(v, st, dr) rbegin(v) + st, rbegin(v) + dr
#define pb push_back
#define pf push_front
#define eb emplace_back
#define ef emplace_front
#define pob pop_back
#define pof pop_front
#define fs first
#define sd second
#define inf 0x7f7f7f7f
#define infll 0xfffffffffffffff
#define sz(v) (int)v.size()

constexpr int varianta = 1; ///1 - KMP, 2 - Rabin-Karp
constexpr int N = 2e6 + 5;
constexpr ull baza = 131;
constexpr ull mod = (ull)(1e9 + 7);

int n, m, q, nr;
string s, t;
vector<int> poz(1024);

void creare_prefix(vector<int>& lps) {
    int q = 0;
    lps[0] = 0;

    for (int i = 1; i < m; ++i) {
        while (q && t[q] != t[i]) {
            q = lps[q - 1];
        }

        if (t[q] == t[i]) {
            ++q;
        }

        lps[i] = q;
    }
}

void prec_hash(vector<ull>& h, vector<ull>& pw) {
    pw[0] = 1;
    for (int i = 1; i <= n; ++i) {
        pw[i] = (pw[i - 1] * baza) % mod;
    }

    for (int i = 1; i <= n; ++i) {
        h[i] = (h[i - 1] * baza + s[i - 1]) % mod;
    }
}

signed main() {
    FAST
    freopen("strmatch.in", "r", stdin);
    freopen("strmatch.out", "w", stdout);

    ///de facut cu KMP Search (LPS) si cu Rabin-Karp (hash-map)

    if (varianta == 1) { ///cu KMP
        cin >> t >> s;
        n = sz(s);
        m = sz(t);
        vector<int> lps(N);
        creare_prefix(lps);

        for (int i = 0; i < n; ++i) {
            while (q && t[q] != s[i]) {
                q = lps[q - 1];
            }

            if (t[q] == s[i]) {
                ++q;
            }

            if (q == m) {
                q = lps[m - 1];
                nr++;

                if (nr <= 1000) {
                    poz[nr] = i - m + 1;
                }
            }
        }
    } else { ///cu Rabin-Karp
        cin >> t >> s;
        n = sz(s);
        m = sz(t);
        vector<ull> h(N), pw(N);
        prec_hash(h, pw);

        auto get_hash = [&](int l, int r) {
            return (h[r + 1] + mod - (h[l] * pw[r - l + 1]) % mod) % mod;
        };

        ull hash_t = 0;
        for (char c : t) {
            hash_t = (hash_t * baza + c) % mod;
        }

        for (int i = 0; i + m <= n; ++i) {
            if (get_hash(i, i + m - 1) == hash_t) {
                nr++;

                if (nr <= 1000) {
                    poz[nr] = i;
                }
            }
        }
    }

    cout << nr << "\n";
    for (int i = 1; i <= min(1000, nr); ++i) {
        cout << poz[i] << " \n"[i == min(1000, nr)];
    }
}