Cod sursa(job #3237374)

Utilizator McMeatGhenea Radu Stefan McMeat Data 8 iulie 2024 17:52:05
Problema Range minimum query Scor 70
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.13 kb
#include <bits/stdc++.h>
using namespace std;
int r[1000][100000], e[100000], n, v[100000];

ifstream f("rmq.in");
ofstream g("rmq.out");
#define cin f
#define cout g



int rmq(int st, int dr)
{
    int x=e[dr-st+1];
    if(v[r[x][st]] > v[r[x][dr-(1<<x)+1]])
        return r[x][dr-(1<<x)+1];
    return r[x][st];
}

int main()
{
    int m;
    cin>>n>>m;
    for(int i=1;i<=n;i++)
    {
        cin>>v[i];
    }

    for(int i=1;i<=n;i++)
        r[0][i]=i;
    int p;
    for(p=1;(1<<p)<=n;p++)
    {
        for(int i=1;i<=n;i++)
        {
            r[p][i]=r[p-1][i];
            int a=i+(1<<(p-1));
            if(a<=n && v[r[p][i]]>v[r[p-1][a]])
                r[p][i]=r[p-1][a];
        }
    }
    /*for(int i=0;i<=p;i++)
    {
        for(int j=1;j<=n;j++)
        {
            cout<<r[i][j]<<" ";
        }
        cout<<endl;
    }*/
    e[1]=0;
    for(int i=2;i<=n;i++)
    {
        e[i]=1+e[i/2];
    }
    int st, dr;
    for(int i=1;i<=m;i++)
    {
        cin>>st>>dr;
        cout<<v[rmq(st, dr)]<<'\n';
    }

    return 0;
}


/*

     9 3 6 2 1 5 7 8 4

*/