Cod sursa(job #2789142)

Utilizator Diana_ManiuManiu Diana Diana_Maniu Data 26 octombrie 2021 22:33:35
Problema Range minimum query Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.86 kb
#include <bits/stdc++.h>

using namespace std;

ifstream fin("rmq.in");
ofstream fout("rmq.out");

int n, m, a[100005], rmq[100005][18], lg[100005];

int query(int st, int dr)
{
    int k = lg[dr - st + 1];
    return min(rmq[st][k], rmq[dr - (1 << k) + 1][k]);
}

void solve()
{
    fin >> n >> m;
    lg[1] = 0;
    for(int i = 2; i <= n; i ++)
    {
        lg[i] = lg[i/2] + 1;
    }

    for(int i = 1; i <= n; i ++)
    {
        fin >> a[i];
        rmq[i][0] = a[i];
    }


    for(int k = 1; k < 18; k ++)
    {
        for(int i = 1; i + (1 << k) - 1 <= n ; i ++)
            rmq[i][k] = min(rmq[i][k - 1], rmq[i + (1 << (k - 1))][k - 1]);
    }

    for(int i = 1; i <= m; i ++)
    {
        int st, dr;
        fin >> st >> dr;
        fout << query(st, dr) << '\n';
    }
}

int main()
{
    solve();
    return 0;
}