Cod sursa(job #1300175)

Utilizator Al3ks1002Alex Cociorva Al3ks1002 Data 24 decembrie 2014 02:25:25
Problema Range minimum query Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.23 kb
#include<cstdio>
#include<fstream>
#include<iostream>
#include<iomanip>
#include<algorithm>
#include<vector>
#include<bitset>
#include<deque>
#include<queue>
#include<set>
#include<map>
#include<cmath>
#include<cstring>
#include<ctime>
#include<cstdlib>
#include<unordered_map>

#define ll long long
#define pb push_back
#define mp make_pair
#define pii pair<int,int>
#define pll pair<ll,ll>

using namespace std;

const int lmax = 17;
const int nmax = 100005;

int n, m, i, j, p, x, y, lg[nmax], rmq[lmax][nmax];

void build()
{
    for(i = 1, p = 2; p <= n; i++, p *= 2)
        for(j = 1; j + p - 1 <= n; j++)
            rmq[i][j] = min(rmq[i - 1][j], rmq[i - 1][j + p / 2]);

    lg[1] = 0;
    for(i = 2; i <= n; i++)
        lg[i] = lg[i / 2] + 1;
}

int query(int x, int y)
{
    int dif = y - x + 1;
    int l = lg[dif];

    return min(rmq[l][x], rmq[l][y - (1 << l) + 1]);
}

int main()
{
    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]);

    build();

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

    return 0;
}