Cod sursa(job #2465628)

Utilizator ElizaTElla Rose ElizaT Data 30 septembrie 2019 17:33:35
Problema Range minimum query Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1 kb
#include <bits/stdc++.h>

using namespace std;

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

int arb[400005],v[100005],ans;

void build(int nod, int st, int dr) {
    if (st == dr)
        arb[nod] = v[st];
    else {
        int md = (st + dr) / 2;
        build(2 * nod, st, md);
        build(2 * nod + 1, md + 1, dr);
        arb[nod] = min(arb[nod * 2 + 1], arb[nod * 2]);
    }
}
void query(int nod, int st, int dr, int a, int b) {
    if (a <= st && dr <= b)
        ans = min(ans, arb[nod]);
    else {
        int md = (st + dr) / 2;
        if (a <= md)
            query (2 * nod, st, md, a, b);
        if (md + 1 <= b)
            query (2 * nod + 1, md + 1, dr, a, b);
    }
}
int main() {
    int n,m,a,b;
    fin >> n >> m;
    for (int i = 1;i <= n;i++)
        fin >> v[i];
    build(1, 1, n);
    for (int i = 1; i <= m; i++){
        fin >> a >> b;
        ans = 100005;
        query(1, 1, n, a, b);
        fout << ans << '\n';
    }
    return 0;
}