Submission #1179836

#	Time	Username	Problem	Language	Result	Execution time	Memory
1179836		Zbyszek99	The Kingdom of JOIOI (JOI17_joioi)	C++20	100 / 100	454 ms	94384 KiB

joioi

#include <bits/stdc++.h>
#define ll long long
#define ff first
#define ss second
#define vl vector<long long>
#define vi vector<int>
#define pii pair<int,int>
#define pll pair<long long, long long>
#define pb push_back
#define rep(i, b) for(int i = 0; i < (b); ++i)
#define rep2(i,a,b) for(int i = a; i <= (b); ++i)
#define rep3(i,a,b,c) for(int i = a; i <= (b); i+=c)
#define count_bits(x) __builtin_popcountll((x))
#define all(x) (x).begin(),(x).end()
#define siz(x) (int)(x).size()
#define forall(it,x) for(auto& it:(x))
using namespace std;
//mt19937 mt;void random(){mt.seed(chrono::time_point_cast<chrono::milliseconds>(chrono::high_resolution_clock::now()).time_since_epoch().count());}
//ll rand(ll a, ll b) {return a + (mt() % (b-a+1));}
const int INF = 1e9+50;
const ll INF_L = 1e18+40;
const ll MOD = 1e9+7;

int arr[2000][2000];
int max_up[2000][2000];
int min_up[2000][2000];
int max_down[2000][2000];
int min_down[2000][2000];
int dp[2001][2001];

int main()
{
    ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
    //random();
    int n,m;
    cin >> n >> m;
    rep(i,n) rep(j,m) cin >> arr[i][j];
    int max_val = 0;
    int min_val = 1e9;
    rep(i,n) rep(j,m)
    {
        max_val = max(max_val,arr[i][j]);
        min_val = min(min_val,arr[i][j]);
    }
    int ans = max_val - min_val;
    rep(i,n)
    {
        rep(j,m)
        {
            max_up[i][j] = arr[i][j];
            min_up[i][j] = arr[i][j];
            if(i != 0)
            {
                max_up[i][j] = max(max_up[i][j],max_up[i-1][j]);
                min_up[i][j] = min(min_up[i][j],min_up[i-1][j]);
            }
        }
    }    
    for(int i = n-1; i >= 0; i--)
    {
        for(int j = m-1; j >= 0; j--)
        {
            max_down[i][j] = arr[i][j];
            min_down[i][j] = arr[i][j];
            if(i != n-1)
            {
                max_down[i][j] = max(max_down[i][j],max_down[i+1][j]);
                min_down[i][j] = min(min_down[i][j],min_down[i+1][j]);
            }
        }
    }
    // max - up, min - down
    rep2(j,1,m)
    {
        rep(i,n+1)
        {
            dp[j][i] = max({dp[j-1][i],(i != 0 ? abs(max_val - min_up[i-1][j-1]) : 0),(i != n ? abs(min_val - max_down[i][j-1]) : 0)});
            if(i != 0 && min_up[i-1][j-1] == min_val) dp[j][i] = 1e9;
            if(i != n && max_down[i][j-1] == max_val) dp[j][i] = 1e9;
            if(i != 0) dp[j][i] = min(dp[j][i],dp[j][i-1]);
            if(j == m) ans = min(ans,dp[j][i]);
        }
    }
    rep2(j,1,m)
    {
        for(int i = n; i >= 0; i--)
        {
            dp[j][i] = max({dp[j-1][i],(i != 0 ? abs(max_val - min_up[i-1][j-1]) : 0),(i != n ? abs(min_val - max_down[i][j-1]) : 0)});
            if(i != 0 && min_up[i-1][j-1] == min_val) dp[j][i] = 1e9;
            if(i != n && max_down[i][j-1] == max_val) dp[j][i] = 1e9;
            if(i != n) dp[j][i] = min(dp[j][i],dp[j][i+1]);
            if(j == m) ans = min(ans,dp[j][i]);
        }
    }
    // min - up, max - down
    rep2(j,1,m)
    {
        rep(i,n+1)
        {
            dp[j][i] = max({dp[j-1][i],(i != 0 ? abs(min_val - max_up[i-1][j-1]) : 0),(i != n ? abs(max_val - min_down[i][j-1]) : 0)});
            if(i != 0 && max_up[i-1][j-1] == max_val) dp[j][i] = 1e9;
            if(i != n && min_down[i][j-1] == min_val) dp[j][i] = 1e9;
            if(i != 0) dp[j][i] = min(dp[j][i],dp[j][i-1]);
            if(j == m) ans = min(ans,dp[j][i]);
          //  cout << i << " " << j << " " << dp[j][i] << " xd\n";
        }
    }
    rep2(j,1,m)
    {
        for(int i = n; i >= 0; i--)
        {
            dp[j][i] = max({dp[j-1][i],(i != 0 ? abs(min_val - max_up[i-1][j-1]) : 0),(i != n ? abs(max_val - min_down[i][j-1]) : 0)});
            if(i != 0 && max_up[i-1][j-1] == max_val) dp[j][i] = 1e9;
            if(i != n && min_down[i][j-1] == min_val) dp[j][i] = 1e9;
            if(i != n) dp[j][i] = min(dp[j][i],dp[j][i+1]);
            if(j == m) ans = min(ans,dp[j][i]);
         //   cout << j << " " << i << " " << dp[j][i] << " dp\n";
        }
    }
    cout << ans << "\n";
}

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