Cod sursa(job #1820674)

Utilizator vladbatalanBatalan Vlad vladbatalan Data 2 decembrie 2016 00:49:09
Problema Range minimum query Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.06 kb
#include <fstream>

#define Nx 100003

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

int log[20],D[20][Nx];
int n,m,a,b,k;


int log_int(int g)
{
    int l=1,r=18,mi;
    if(g==1)return 0;
    while(l<=r)
    {
        mi=(l+r)/2;
        if(log[mi]<g)
            l=mi+1;
        else
            if(log[mi]>g)
                r=mi-1;
            else
                return mi;
    }
    mi=(l+r)/2;

    return mi;
}


void configurare_rmq(){
    int rnd=log_int(n);
    for(int i=1;i<=rnd;i++)
    {
        for(int j=1;j<=n-(1<<i-1);j++)
        {
            D[i][j]=min(D[i-1][j],D[i-1][j+(1<<(i-1))]);
        }
    }
}

inline void prelucrare_log()
{
    log[0]=1;
    for(int i=1;i<=18;i++){
        log[i]=log[i-1]*2;
    }
}

int main()
{
    fin>>n>>m;
    for(int i=1;i<=n;i++)
        fin>>D[0][i];
    prelucrare_log();
    configurare_rmq();
    while(m--)
    {
        fin>>a>>b;
        k=log_int(b-a);
        fout<<min(D[k][a],D[k][b-(1<<k)+1])<<'\n';
    }
    return 0;
}