Submission #854591

#	Time	Username	Problem	Language	Result	Execution time	Memory
854591		becaido	The Kingdom of JOIOI (JOI17_joioi)	C++17	100 / 100	461 ms	35864 KiB

joioi

#pragma GCC optimize("O3,unroll-loops")
#pragma GCC target("avx,popcnt,sse4,abm")
#include <bits/stdc++.h>
using namespace std;

#ifdef WAIMAI
#define debug(HEHE...) cout << "[" << #HEHE << "] : ", dout(HEHE)
void dout() {cout << '\n';}
template<typename T, typename...U>
void dout (T t, U...u) {cout << t << (sizeof... (u) ? ", " : ""), dout (u...);}
#else
#define debug(...) 7122
#endif

#define ll long long
#define Waimai ios::sync_with_stdio(false), cin.tie(0)
#define FOR(x,a,b) for (int x = a, I = b; x <= I; x++)
#define pb emplace_back
#define F first
#define S second

const int SIZE = 2005;

int n, m;
int a[SIZE][SIZE];

int mx, mn;
int u[SIZE], d[SIZE];

bool ok(int delta) {
    bool f = 1;
    FOR (j, 1, m) {
        u[j] = 0, d[j] = n;
        FOR (i, 1, n) {
            if (mx - delta > a[i][j]) break;
            u[j] = i;
        }
        for (int i = n; i >= 1; i--) {
            if (mn + delta < a[i][j]) break;
            d[j] = i - 1;
        }
        if (u[j] < d[j]) {
            f = 0;
            break;
        }
    }
    if (f) {
        int cur = 0;
        FOR (j, 1, m) {
            cur = max(cur, d[j]);
            if (cur > u[j]) {
                f = 0;
                break;
            }
        }
        if (f) return 1;
        f = 1;
        cur = n;
        FOR (j, 1, m) {
            cur = min(cur, u[j]);
            if (cur < d[j]) {
                f = 0;
                break;
            }
        }
        if (f) return 1;
    }
    f = 1;
    FOR (j, 1, m) {
        u[j] = 0, d[j] = n;
        FOR (i, 1, n) {
            if (mn + delta < a[i][j]) break;
            u[j] = i;
        }
        for (int i = n; i >= 1; i--) {
            if (mx - delta > a[i][j]) break;
            d[j] = i - 1;
        }
        if (u[j] < d[j]) {
            f = 0;
            break;
        }
    }
    if (f) {
        int cur = 0;
        FOR (j, 1, m) {
            cur = max(cur, d[j]);
            if (cur > u[j]) {
                f = 0;
                break;
            }
        }
        if (f) return 1;
        f = 1;
        cur = n;
        FOR (j, 1, m) {
            cur = min(cur, u[j]);
            if (cur < d[j]) {
                f = 0;
                break;
            }
        }
        if (f) return 1;
    }
    return 0;
}

void solve() {
    cin >> n >> m;
    FOR (i, 1, n) FOR (j, 1, m) cin >> a[i][j];

    mn = INT_MAX;
    FOR (i, 1, n) FOR (j, 1, m) {
        mx = max(mx, a[i][j]);
        mn = min(mn, a[i][j]);
    }

    int l = 0, r = mx - mn;
    while (l < r) {
        int mid = (l + r) / 2;
        if (ok(mid)) r = mid;
        else l = mid + 1;
    }
    cout << l << '\n';
}

int main() {
    Waimai;
    solve();
}

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