Cod sursa(job #2670084)

Utilizator maraboneaMara Bonea marabonea Data 8 noiembrie 2020 22:39:11
Problema Range minimum query Scor 40
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.8 kb
/**
infoarena.ro/problema/rmq
Range Minimum Query
*/
#include <fstream>
#include <cstring>
using namespace std;
int n,q;
const int nmax=0x3f3f3f3f3f3f3f3f;
int log2[100010];
int m[20][100010];
void precalc()
{
    for(int i=2;i<=n;i++)
    {
        log2[i]=log2[i/2]+1;
    }
    for(int i=1;(1<<i)<=n;i++)
    {
        for(int j=1;j<=n-(1<<i)+1;j++)
        {
            m[i][j]=min(m[i-1][j],m[i-1][j+(1<<(i-1))]);
        }
    }
}
int main()
{
    ifstream fin("rmq.in");
    ofstream fout("rmq.out");
    fin>>n>>q;
    memset(m,nmax,sizeof m);
    for(int i=1; i<=n; i++)
    {
        fin>>m[0][i];
    }
    precalc();
    int x,y;
    while( fin>>x>>y)
    {
        int p=log2[y-x+1];
        fout<<min(m[p][x],m[p][y-(1<<p)+1])<<endl;
    }
    return 0;
}