Cod sursa(job #2803679)

Utilizator andrei.eEnachescu Andrei andrei.e Data 20 noiembrie 2021 12:34:53
Problema Datorii Scor 0
Compilator cpp-64 Status done
Runda Arhiva de probleme Marime 1.39 kb
#include <fstream>
using namespace std;

ifstream in ("arbint.in");
ofstream out ("arbint.out");

int n, m, v[15001], a[100001];

void build (int nod, int s, int d)
{
    if (s == d)
    {
        a[nod] = v[s];
        return;
    }
    int m = (s + d) / 2;
    build(nod * 2, s, m);
    build(nod * 2 + 1, m + 1, d);
    a[nod] = a[nod * 2] + a[nod * 2 + 1];
}

void update (int nod, int s, int d, int poz, int val)
{
    if (s == d)
    {
        a[nod] = max(a[nod] - val, 0);
        return;
    }
    int m = (s + d) / 2;
    if (poz <= m)
        update (nod * 2, s, m, poz, val);
    else
        update (nod * 2 + 1, m + 1, d, poz, val);
    a[nod] = a[nod * 2] + a[nod * 2 + 1];
}

int query (int nod, int s, int d, int l, int r)
{
    if (d < l || s > r)
        return 0;

    if (l <= s && d <= r)
        return a[nod];

    int m = (s + d) / 2;
    return query(nod * 2, s, m, l, r) + query(nod * 2 + 1, m + 1, d, l, r);
}

int main()
{
    in >> n >> m;

    for (int i = 1; i <= n; i++)
        in >> v[i];

    build (1, 1, n);

    int tip, x, y;
    for (int i = 1; i <= m; i++)
    {
        in >> tip >> x >> y;

        if (tip == 0)
        {
            update (1, 1, n, x, y);
        }
        else
        {
            out << query(1, 1, n, x, y) << '\n';
        }
    }

    in.close();
    out.close();
    return 0;
}