Cod sursa(job #1167429)

Utilizator mirceadinoMircea Popoveniuc mirceadino Data 4 aprilie 2014 23:22:18
Problema Range minimum query Scor 0
Compilator cpp Status done
Runda Arhiva educationala Marime 0.98 kb
#include<cstdio>
#include<algorithm>

using namespace std;

const int NMAX = 100000+5;
const int LMAX = 18;

void Read(),Build(),Solve();

int N,M;
int RMQ[LMAX][NMAX];

int Query(int x,int y)
{
    int dist,step,p;

    dist = y - x + 1;
    for(step = 0; (1<<step) < dist; step++);
    step >>= 1;
    p = 1<<step;

    return min(RMQ[step][x], RMQ[step][y-p+1]);
}

int main()
{
    Read();
    Build();
    Solve();

    return 0;
}

void Read()
{
    int i;

    freopen("rmq.in","r",stdin);
    freopen("rmq.out","w",stdout);

    scanf("%d%d",&N,&M);

    for(i = 1; i <= N; i++)
        scanf("%d",&RMQ[0][i]);
}

void Build()
{
    int i,step;

    for(step = 1; (1<<step) <= N; step++)
        for(i = 1; i <= N - step + 1; i++)
            RMQ[step][i] = min(RMQ[step-1][i], RMQ[step-1][i+step]);
}

void Solve()
{
    int x,y;

    for(; M; --M)
    {
        scanf("%d%d",&x,&y);
        printf("%d\n",Query(x,y));
    }
}