Cod sursa(job #1168689)

Utilizator mirceadinoMircea Popoveniuc mirceadino Data 9 aprilie 2014 11:44:13
Problema Range minimum query Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 0.97 kb
#include<cstdio>
#include<algorithm>

using namespace std;

const int NMAX = 100000+5;
const int LMAX = 17;

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

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

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

    for(step = 1, p = 2; p <= N; step++, p <<= 1)
        for(i = 1; i + (p>>1) <= N; i++)
            RMQ[step][i] = min(RMQ[step-1][i], RMQ[step-1][i+(p>>1)]);
}

void Solve()
{
    int x,y;

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