Cod sursa(job #3249889)

Utilizator TeodorVTeodorV TeodorV Data 18 octombrie 2024 18:07:37
Problema Range minimum query Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.85 kb
#include <bits/stdc++.h>

using namespace std;

ifstream fin("rmq.in");
ofstream fout("rmq.out");

const int Nmax=100001;
const int RMQmax=log2(Nmax)+2;

int rmq[Nmax][RMQmax];///rmq[i][j]=min(v[i], .... v[i+(1<<j)-1])

int n;
int v[Nmax];

void initRMQ()
{

    for(int i=1; i<=n; i++)
        rmq[i][0]=v[i];

    for(int j=1; (1<<j)<=n; j++)
    {
        for(int i=1; i+(1<<j)-1<=n; i++)
        {
            rmq[i][j]=min(rmq[i][j-1], rmq[i+(1<<(j-1))][j-1]);
        }
    }
}
int query(int st, int dr)
{
    int p2=log2(dr-st+1);
    return min(rmq[st][p2], rmq[dr-(1<<p2)+1][p2]);
}

int main()
{
    int m;
    fin>>n>>m;
    for(int i=1; i<=n; i++)
        fin>>v[i];
    initRMQ();
    int st,dr;
    for(int q=1; q<=m; q++)
    {
        fin>>st>>dr;
        fout<<query(st, dr)<<'\n';
    }
    return 0;
}