Cod sursa(job #3220641)

Utilizator eduardbuchmaneduardbuchman eduardbuchman Data 4 aprilie 2024 15:33:11
Problema Datorii Scor 100
Compilator cpp-64 Status done
Runda Arhiva de probleme Marime 1.44 kb
#include <fstream>
#define NMAX 15000
using namespace std;

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

int sume[NMAX + 5], aint[4 * NMAX + 5];

void build(int st, int dr, int nod) {
    if (st == dr)
        aint[nod] = sume[st];
    else {
        int mij = (st + dr) / 2;
        build(st, mij, nod * 2);
        build(mij + 1, dr, nod * 2 + 1);
        aint[nod] = aint[nod * 2] + aint[nod * 2 + 1];
    }
}

void update(int st, int dr, int nod, int poz, int val) {
    if (st == dr)
        aint[nod] -= val;
    else {
        int mij = (st + dr) / 2;
        if (poz <= mij)
            update(st, mij, 2 * nod, poz, val);
        else
            update(mij + 1, dr, 2 * nod + 1, poz, val);
        aint[nod] = aint[nod * 2] + aint[nod * 2 + 1];
    }
}

int query(int st, int dr, int nod, int i, int j) {
    if (i <= st && dr <= j)
        return aint[nod];
    int mij = (st + dr) / 2, s = 0;
    if (i <= mij)
        s += query(st, mij, nod * 2, i, j);
    if (mij < j)
        s += query(mij + 1, dr, nod * 2 + 1, i, j);
    return s;
}

int main()
{
    int n, m;
    in >> n >> m;
    for (int i = 1; i <= n; i++)
        in >> sume[i];
    build(1, n, 1);
    for (int i = 1; i <= m; i++) {
        int caz, x, y;
        in >> caz >> x >> y;
        if (!caz)
            update(1, n, 1, x, y);
        else
            out << query(1, n, 1, x, y) << '\n';
    }
    return 0;
}