Submission #862889

#	Time	Username	Problem	Language	Result	Execution time	Memory
862889		green_gold_dog	The Kingdom of JOIOI (JOI17_joioi)	C++17	100 / 100	2156 ms	188288 KiB

joioi

#pragma GCC optimize("Ofast")
//#pragma GCC target("avx,avx2,sse,sse2,sse3,ssse3,sse4,abm,popcnt,mmx")
#include <bits/stdc++.h>

using namespace std;

typedef int ll;
typedef double db;
typedef long double ldb;
typedef complex<double> cd;

constexpr ll INF64 = 9'000'000'000'000'000'000, INF32 = 2'000'000'000, MOD = 1'000'000'007;
constexpr db PI = acos(-1);
constexpr bool IS_FILE = false, IS_TEST_CASES = false;

random_device rd;
mt19937 rnd32(rd());
mt19937_64 rnd64(rd());

template<typename T>
bool assign_max(T& a, T b) {
        if (b > a) {
                a = b;
                return true;
        }
        return false;
}

template<typename T>
bool assign_min(T& a, T b) {
        if (b < a) {
                a = b;
                return true;
        }
        return false;
}

template<typename T>
T square(T a) {
        return a * a;
}

template<>
struct std::hash<pair<ll, ll>> {
        ll operator() (pair<ll, ll> p) const {
                return ((__int128)p.first * MOD + p.second) % INF64;
        }
};

ll get(set<pair<ll, pair<ll, ll>>>& s) {
        if (s.empty()) {
                return 0;
        }
        return s.rbegin()->first - s.begin()->first;
}

ll sol(ll n, ll m, vector<vector<ll>>& arr) {
        vector<tuple<ll, ll, ll>> s1;
        vector<vector<ll>> dels;
        ll mi = INF32, ma = 0;
        for (ll i = 0; i < n; i++) {
                for (ll j = 0; j < m; j++) {
                        s1.emplace_back(arr[i][j], i, j);
                }
        }
        sort(s1.rbegin(), s1.rend());
        vector<ll> col(n, m - 1);
        vector<vector<pair<ll, ll>>> del;
        vector<ll> ans(1, 0);
        for (auto[_, x, y] : s1) {
                if (col[x] < y) {
                        continue;
                }
                del.emplace_back(0);
                for (ll j = x; j < n; j++) {
                        if (col[j] < y) {
                                break;
                        }
                        while (col[j] >= y) {
                                del.back().emplace_back(j, col[j]);
                                assign_max(ma, arr[j][col[j]]);
                                assign_min(mi, arr[j][col[j]]);
                                col[j]--;
                        }
                }
                ans.push_back(ma - mi);
        }
        mi = INF32;
        ma = 0;
        ll na = ans.back();
        while (!del.empty()) {
                for (auto[x, y] : del.back()) {
                        assign_max(ma, arr[x][y]);
                        assign_min(mi, arr[x][y]);
                }
                del.pop_back();
                ans.pop_back();
                assign_min(na, max(ans.back(), ma - mi));
        }
        return na;
}

void solve() {
        ll n, m;
        cin >> n >> m;
        vector<vector<ll>> arr(n, vector<ll>(m));
        for (ll i = 0; i < n; i++) {
                for (ll j = 0; j < m; j++) {
                        cin >> arr[i][j];
                }
        }
        ll ans = INF32;
        for (ll i = 0; i < 2; i++) {
                reverse(arr.begin(), arr.end());
                for (ll j = 0; j < 2; j++) {
                        for (auto& k : arr) {
                                reverse(k.begin(), k.end());
                        }
                        assign_min(ans, sol(n, m, arr));
                }
        }
        cout << ans << '\n';
}

int main() {
        if (IS_FILE) {
                freopen("", "r", stdin);
                freopen("", "w", stdout);
        }
        ios_base::sync_with_stdio(false);
        cin.tie(0);
        cout.tie(0);
        ll t = 1;
        if (IS_TEST_CASES) {
                cin >> t;
        }
        for (ll i = 0; i < t; i++) {
                solve();
        }
}

Compilation message (stderr)

joioi.cpp:12:22: warning: overflow in conversion from 'long int' to 'll' {aka 'int'} changes value from '9000000000000000000' to '-494665728' [-Woverflow]
   12 | constexpr ll INF64 = 9'000'000'000'000'000'000, INF32 = 2'000'000'000, MOD = 1'000'000'007;
      |                      ^~~~~~~~~~~~~~~~~~~~~~~~~
joioi.cpp: In function 'int main()':
joioi.cpp:127:24: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  127 |                 freopen("", "r", stdin);
      |                 ~~~~~~~^~~~~~~~~~~~~~~~
joioi.cpp:128:24: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  128 |                 freopen("", "w", stdout);
      |                 ~~~~~~~^~~~~~~~~~~~~~~~~

• Subtask 1: 15 / 15
• Subtask 2: 45 / 45
• Subtask 3: 40 / 40