Submission #399702

#	Time	Username	Problem	Language	Result	Execution time	Memory
399702		SavicS	The Kingdom of JOIOI (JOI17_joioi)	C++14	0 / 100	1 ms	336 KiB

joioi

#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#include <bits/stdc++.h>

#define fi first
#define se second
#define pb push_back
#define sz(a) (int)a.size()
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
#define ff(i,a,b) for(int i=a;i<=b;i++)
#define fb(i,b,a) for(int i=b;i>=a;i--)

using namespace std;
using namespace __gnu_pbds;
typedef long long ll;
typedef pair<int,int> pii;
const int maxn = 2005;
const int inf = 1e9 + 5;

template<typename T>
using ordered_set = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;

// os.order_of_key(k) the number of elements in the os less than k
// *os.find_by_order(k)  print the k-th smallest number in os(0-based)

int n, m;
int mat[maxn][maxn];

int ide[maxn];
bool check(int X) {

	memset(ide, 0, sizeof(ide));

    // opadajacu
    {
        ide[0] = inf;

        int mn = inf, mx = 0;
        ff(i,1,n) {

            int pommx = mx, pommn = mn;
            ff(j,1,m) {

                pommx = max(pommx, mat[i][j]);
                pommn = min(pommn, mat[i][j]);

                if(pommx - pommn > X)break;
                mx = pommx, mn = pommn;
                ide[i] = j;

            }

            ide[i] = min(ide[i], ide[i - 1]);

        }

        int najv = 0, najm = inf;
        ff(i,1,n) {
            ff(j,ide[i] + 1,m) {
                najv = max(najv, mat[i][j]);
                najm = min(najm, mat[i][j]);
            }
        }

        if(najv - najm <= X)return 1;

    }

	memset(ide, 0, sizeof(ide));

    // rastuce
    {
        ide[n + 1] = inf;

        int mn = inf, mx = 0;
        fb(i,n,1) {

            int pommx = mx, pommn = mn;
            ff(j,1,m) {

                pommx = max(pommx, mat[i][j]);
                pommn = min(pommn, mat[i][j]);

                if(pommx - pommn > X)break;
                mx = pommx, mn = pommn;
                ide[i] = j;

            }

            ide[i] = min(ide[i], ide[i + 1]);

        }

        int najv = 0, najm = inf;
        ff(i,1,n) {
            ff(j,ide[i] + 1,m) {
                najv = max(najv, mat[i][j]);
                najm = min(najm, mat[i][j]);
            }
        }

        if(najv - najm <= X)return 1;

    }

    return 0;

}

int main() 
{
    ios::sync_with_stdio(false);
    cout.tie(nullptr);
    cin.tie(nullptr);
    cin >> n >> m;
    ff(i,1,n)ff(j,1,m)cin >> mat[i][j];

    int l = 0, r = inf, ans = 0;
    while(l <= r) {
        int mid = (l + r) / 2;
        if(check(mid)) {
            r = mid - 1;
            ans = mid;
        } else l = mid + 1;
    }

    cout << ans << endl;

    return 0;
}
/**



// probati bojenje sahovski ili slicno

**/

• Subtask 1: 0 / 15
• Subtask 2: 0 / 45
• Subtask 3: 0 / 40