Cod sursa(job #2501903)

Utilizator hurjui12AlexandruHurjui Alexandru-Mihai hurjui12Alexandru Data 30 noiembrie 2019 11:53:38
Problema Range minimum query Scor 80
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.13 kb
#include <bits/stdc++.h>
using namespace std;

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

int arb[1<<18];

void update(int nod, int poz, int val, int st, int dr)
{
    if (st == dr)
        arb[nod] = val;
    else
    {
        int mij = (st+dr)>>1;
        if (poz <= mij)
            update(nod << 1, poz, val, st, mij);
        else
            update(nod << 1|1, poz, val, mij+1, dr);
        arb[nod] = min(arb[nod<<1], arb[nod<<1|1]);
    }
}

int query(int nod, int a, int b, int st, int dr)
{
    if (a <= st && dr <= b)
        return arb[nod];
    else
    {
        int mij = (st+dr)>>1, alfa, beta;
        alfa = beta = 1<<30;
        if (a <= mij)
            alfa = query(nod<<1, a, b, st, mij);
        if (b > mij)
            beta = query(nod << 1|1, a, b, mij+1,dr);
        return min(alfa, beta);
    }
}

int main()
{
    int n, m, i, x, y;
    fin >> n >> m;
    for (i = 1; i<=n; i++)
    {
        fin >> x;
        update(1, i, x, 1, n);
    }
    for (i = 1; i<=m; i++)
    {
        fin >> x >> y;
        fout << query(1, x, y, 1, n) << '\n';
    }
    return 0;
}