Cod sursa(job #2903802)

Utilizator fredtuxFlorin Dinu fredtux Data 17 mai 2022 20:34:17
Problema Range minimum query Scor 40
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.14 kb
#include <fstream>

using namespace std;

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

int arb[400004];

inline unsigned int
arbQry(int n, int st, int dr, int x, int y) {
    int st2, dr2, mid;
    dr2 = st2 = 1000005;

    if (st >= x && dr <= y)
        return arb[n];

//    mid = st + (dr - st) / 2;
    mid = (st + dr) >> 1;

    if (x <= mid) {
        st2 = arbQry((n << 1), st, mid, x, y);
    }

    if (y > mid) {
        dr2 = arbQry(-(~(n << 1)), mid + 1, dr, x, y);
    }

    return min(dr2, st2);
}

inline void arbUpd(int n, int st, int dr, int p, int val) {
    if (st == dr) {
        arb[n] = val;
        return;
    }

//    int mid = st + (dr - st) / 2;
    int mid = (st + dr) >> 1;
    if (p <= mid) {
        arbUpd((n << 1), st, mid, p, val);
    } else {
        arbUpd((n << 1) + 1, mid + 1, dr, p, val);
    }

    arb[n] = min(arb[(n << 1)], arb[-(~(n << 1))]);
}

int main() {
    int n, m, i, x, y;

    fin >> n >> m;

    for (i = 1; i <= n; ++i) {
        fin >> x;
        arbUpd(1, 1, n, i, x);
    }

    for (i = 0; i < m; ++i) {
        fin >> x >> y;
        fout << arbQry(1, 1, n, x, y) << endl;
    }

    return 0;
}