Cod sursa(job #2936802)

Utilizator CarenaMironov Cezar Luca Carena Data 9 noiembrie 2022 15:44:22
Problema Range minimum query Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.78 kb
#include <fstream>
#include <cmath>

using namespace std;

ifstream fin("rmq.in");
ofstream fout("rmq.out");
int v[100000], sp[100000][20];

void BSP(int n, int sp[100000][20], int v[100000], int i, int j)
{
    for(i=0;i<n;i++)
        sp[i][0]=v[i];
    int l=(int)log2(n);
    for(j=1;j<=l;j++)
        for(i=0;i+(1<<(j-1))<n;i++)
            sp[i][j]=min(sp[i][j-1], sp[i+(1<<(j-1))][j-1]);
}

int Query(int x, int y)
{
    int l=y-x+1, p=0;
    while((1<<p)<=l)
        p++;
    p--;
    return min(sp[x-1][p], sp[y-(1<<p)][p]);
}

int main()
{
    int n, m, x, y, i, j;
    fin>>n>>m;
    for(i=0;i<n;i++)
        fin>>v[i];
    BSP(n, sp, v, i, j);
    for(i=1;i<=m;i++)
    {
        fin>>x>>y;
        fout<<Query(x, y)<<'\n';
    }
    return 0;
}