Cod sursa(job #2975777)

Utilizator andreibrosPeta Andrei Mathias andreibros Data 7 februarie 2023 15:21:28
Problema Plantatie Scor 10
Compilator cpp-64 Status done
Runda Arhiva de probleme Marime 1.13 kb
#include <iostream>
#include <fstream>
#include <algorithm>
using namespace std;
ifstream in("plantatie.in");
ofstream out("plantatie.out");
const int NMAX=505;
int a[NMAX][NMAX];
int RMQ[20][NMAX][NMAX]; // maximul unei matrici de lungime 2^i;
int lg2[20];
int x,y,l;
int query()
{
    int x2=x+l-1;
    int y2=y+l-1;
    int lg=lg2[x2-x+1];
    y2-=(1<<lg)-1;
    x2-=(1<<lg)-1;
    return max(max({RMQ[lg][x][y], RMQ[lg][x2][y], RMQ[lg][x][y2]}), RMQ[lg][x2][y2]);
}
int main()
{
    int n,m;
    in>>n>>m;
    for(int i=1; i<=n; i++)
        for(int j=1; j<=n; j++)
    {
        in>>a[i][j];
        RMQ[0][i][j]=a[i][j];
    }
    lg2[1]=0;
    for(int i=2; i<15; i++)
        lg2[i]=lg2[i/2]+1;
    for(int k=1; k<=lg2[n]; k++)
    {
        for(int i=1,ii;(ii=i+(1<<(k-1)))<=n; i++ )
        {
            for(int j=1,jj;(jj=j+(1<<(k-1)))<=n; j++)
            {
                RMQ[k][i][j]=max({RMQ[k-1][i][j], RMQ[k-1][ii][j], RMQ[k-1][i][jj], RMQ[k-1][ii][jj]});
            }
        }
    }

    for(int i=1; i<=m; i++)
    {
        in>>x>>y>>l;
        out<<query()<<"\n";
    }
    return 0;
}