Cod sursa(job #2670094)

Utilizator maraboneaMara Bonea marabonea Data 8 noiembrie 2020 22:59:31
Problema Range minimum query Scor 40
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.83 kb
#include <iostream>
#include <fstream>
#include <cstring>

using namespace std;

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

const int nmax=0x3f3f3f3f3f3f3f3f;
int n,q;
int log2[100020], m[100020][20];

void logaritm()
{
    log2[1] = 0;
    for(int i=2;i<=n;i++)
        log2[i]=log2[i/2]+1;
}

void precalc()
{
    for(int j=1;(1<<j)<=n;j++)
        for(int i=1;i+(1<<j)<=n+1;i++)
            m[i][j]=min(m[i][j-1],m[i+(1<<(j-1))][j-1]);
}

int interv(int x,int y)
{
    int p=y-x+1;
    return min(m[x][log2[p]],m[y-(1<<log2[p])+1][log2[p]]);
}

int main()
{
    fin>>n>>q;
    memset(m,nmax,sizeof m);
    for(int i=1;i<=n;i++)
        fin>>m[i][0];
    logaritm();
    precalc();
    while(q--)
    {
        int x,y;
        fin>>x>>y;
        fout<<interv(x,y)<<endl;
    }

    return 0;
}