Cod sursa(job #1376701)

Utilizator Al3ks1002Alex Cociorva Al3ks1002 Data 5 martie 2015 18:25:13
Problema Range minimum query Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.27 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>
#define all(x) (x).begin(), (x).end()
#define fi first
#define se second

using namespace std;

const int nmax = 100005;
const int lmax = 18;

int n, q, i, j, p, a, b, lg[nmax], rmq[lmax][nmax];

int query(int a, int b)
{
    int dif = b - a + 1;
    int p = lg[dif];

    return min(rmq[p][a], rmq[p][b - (1 << p) + 1]);
}

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

    scanf("%d%d", &n, &q);

    for(i = 1; i <= n; i++)
        scanf("%d", &rmq[0][i]);

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

    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]);

    for(; q; q--)
    {
        scanf("%d%d", &a, &b);
        printf("%d\n", query(a, b));
    }

    return 0;
}