Cod sursa(job #2983357)

Utilizator andreipirjol5Andrei Pirjol andreipirjol5 Data 22 februarie 2023 11:26:58
Problema Datorii Scor 100
Compilator cpp-64 Status done
Runda Arhiva de probleme Marime 2.2 kb
#include <fstream>
#include <vector>
#include <cmath>

using namespace std;
ifstream fin ("datorii.in");
ofstream fout ("datorii.out");

const int NMAX = 15000;
int v[NMAX + 5];
int rightmax, n;
vector <int> aint;

void build(int node = 1, int left = 1, int right = rightmax)
{
    if(left == right and left > n)
    {
        aint[node] = 0;
        return;
    }

    if(left == right)
    {
        aint[node] = v[left];
        return;
    }

    int mid = (left + right) / 2;

    build(2 * node, left, mid);
    build(2 * node + 1, mid + 1, right);

    aint[node] = aint[2 * node] + aint[2 * node + 1];
}

void update(int pos, int value, int node = 1, int left = 1, int right = rightmax)
{
    if(left == right and left > n)
    {
        aint[node] = 0;
        return;
    }

    if(left == right)
    {
        aint[node] -= value;
        return;
    }

    int mid = (left + right) / 2;

    if(pos <= mid)
        update(pos, value, 2 * node, left, mid);

    if(pos > mid)
        update(pos, value, 2 * node + 1, mid + 1, right);

    aint[node] = aint[2 * node] + aint[2 * node + 1];
}

int query(int left_q, int right_q, int node = 1, int left = 1, int right = rightmax)
{
    if(left_q <= left and right <= right_q)
        return aint[node];

    int mid = (left + right) / 2;
    int leftans = 0, rightans = 0;

    if(left_q <= mid)
        leftans += query(left_q, right_q, 2 * node, left, mid);

    if(mid < right_q)
        rightans += query(left_q, right_q, 2 * node + 1, mid + 1, right);

    return leftans + rightans;
}

int main()
{
    int q;
    fin >> n >> q;

    int exp = log2(n), nodes;
    if((1 << exp) == n)
        nodes = 2 * (1 << exp) - 1;
    else
    {
        exp++;
        nodes = 2 * (1 << exp) - 1;
    }
    aint.resize(nodes + 5);
    rightmax = 1 << exp;

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

    build();

    for(int i = 1; i <= q; i++)
    {
        int op, x, y;
        fin >> op >> x >> y;

        if(op == 0)
            update(x, y);
        else if(op == 1)
            fout << query(x, y) << '\n';
    }

    fin.close();
    fout.close();
    return 0;
}