제출 #503268

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
503268		Victor	Necklace (Subtask 1-3) (BOI19_necklace1)	C++17	0 / 85	1 ms	332 KiB

necklace

// #pragma GCC target ("avx,avx2,fma")
// #pragma GCC optimize ("Ofast,inline") // O1 - O2 - O3 - Os - Ofast
// #pragma GCC optimize ("unroll-loops")
#include <bits/stdc++.h>

using namespace std;

#define rep(i, a, b) for (int i = (a); i < (b); ++i)
#define per(i, a, b) for (int i = (b - 1); i >= (a); --i)
#define trav(a, x) for (auto &a : x)

#define all(x) x.begin(), x.end()
#define sz(x) x.size()
#define pb push_back
#define debug(x) cout << #x << " = " << x << endl

#define umap unordered_map
#define uset unordered_set

typedef pair<int, int> ii;
typedef pair<int, ii> iii;
typedef vector<int> vi;
typedef vector<ii> vii;
typedef vector<vi> vvi;

typedef long long ll;
typedef pair<ll, ll> pll;
typedef vector<ll> vll;
typedef vector<pll> vpll;

const ll INF = 1'000'000'007, MAXN = 3000;
const ll num_bases = 2, bases[] = {31, 47};
ll base_pow[num_bases][MAXN];

string jill, jane;

int main() {
    cin.tie(0)->sync_with_stdio(0);
    cin.exceptions(cin.failbit);

    rep(i, 0, num_bases) base_pow[i][0] = 1;
    rep(i, 0, num_bases) rep(j, 1, MAXN) base_pow[i][j] = base_pow[i][j - 1] * bases[i] % INF;

    cin >> jill >> jane;

    map<ii, int> possible;
    int n = min(sz(jill), sz(jane));

    int lo = 0, hi = n;
    int start_jill = 0, start_jane = 0;
    while (lo != hi) {
        int mid = (lo + hi + 1) / 2;

        vll hash_val = {0, 0};
        rep(j, 0, num_bases) rep(i, 0, mid - 1) hash_val[j] = (hash_val[j] * bases[j] + jill[i]) % INF;
        rep(i, mid - 1, sz(jill)) {
            rep(j, 0, num_bases) hash_val[j] = (hash_val[j] * bases[0] + jill[i]) % INF;

            possible.insert({{hash_val[0], hash_val[1]}, i - mid + 1});
            rep(j, 0, num_bases) hash_val[j] = ((hash_val[j] - base_pow[j][mid - 1] * jill[i - mid + 1]) % INF + INF) % INF;
        }

        int sjill = -1, sjane = -1;
        rep(k, 0, 2) {
            hash_val = {0, 0};
            rep(j, 0, num_bases) rep(i, 0, mid - 1) hash_val[j] = (hash_val[j] * bases[j] + jane[i]) % INF;
            rep(i, mid - 1, sz(jane)) {
                rep(j, 0, num_bases) hash_val[j] = (hash_val[j] * bases[0] + jane[i]) % INF;

                vll tmp_val = hash_val;
                rep(j, 0, mid) {
                    if (possible.count({tmp_val[0], tmp_val[1]})) {
                        if (k) {
                            sjane = i - mid + 1;
                            sjane = sz(jane) - sjane;
                            sjane -= mid;
                        } else
                            sjane = i - mid + 1;
                        sjill = possible[{tmp_val[0], tmp_val[1]}];
                    }

                    rep(base, 0, 2) {
                        tmp_val[base] = ((tmp_val[base] - base_pow[base][mid - 1] * jane[i - mid + 1 + j]) % INF + INF) % INF;
                        tmp_val[base] = (tmp_val[base] * bases[base] + jane[i - mid + 1 + j]) % INF;
                    }
                }

                rep(j, 0, num_bases) hash_val[j] = ((hash_val[j] - base_pow[j][mid - 1] * jane[i - mid + 1]) % INF + INF) % INF;
            }
            reverse(all(jane));
        }

        if (sjill == -1)
            hi = mid - 1;
        else {
            lo = mid;
            start_jill = sjill;
            start_jane = sjane;
        }
        possible.clear();
    }

    string s1 = jill.substr(start_jill, lo);
    string s2 = jane.substr(start_jane, lo);
    bool yes = 0;
    rep(k, 0, 2) {
        string cur = s2 + s2;
        rep(i, 0, lo) if (s1 == cur.substr(i, lo)) yes = 1;
        reverse(all(s2));
    }
    cout << lo << endl;
    cout << start_jill << ' ' << start_jane << endl;

    return 0;
}

컴파일 시 표준 에러 (stderr) 메시지

necklace.cpp: In function 'int main()':
necklace.cpp:8:42: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
    8 | #define rep(i, a, b) for (int i = (a); i < (b); ++i)
      |                                          ^
necklace.cpp:56:9: note: in expansion of macro 'rep'
   56 |         rep(i, mid - 1, sz(jill)) {
      |         ^~~
necklace.cpp:8:42: warning: comparison of integer expressions of different signedness: 'int' and 'std::__cxx11::basic_string<char>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
    8 | #define rep(i, a, b) for (int i = (a); i < (b); ++i)
      |                                          ^
necklace.cpp:67:13: note: in expansion of macro 'rep'
   67 |             rep(i, mid - 1, sz(jane)) {
      |             ^~~
necklace.cpp:105:10: warning: variable 'yes' set but not used [-Wunused-but-set-variable]
  105 |     bool yes = 0;
      |          ^~~

• Subtask 1: 0 / 25
• Subtask 2: 0 / 20
• Subtask 3: 0 / 40