Cod sursa(job #1502078)

Utilizator alexandru.ghergutAlexandru-Gabriel Ghergut alexandru.ghergut Data 14 octombrie 2015 09:35:05
Problema Datorii Scor 0
Compilator cpp Status done
Runda Arhiva de probleme Marime 2.01 kb
#include <fstream>
#include <cmath>
using namespace std;

void update(int index, int &val, int &pos, int left, int right, int tree[])
{
    if (left == right)
        tree[index] += val;
    else
    {
        int middle = (left + right) >> 1;
        if (pos <= middle)
            update((index << 1) + 1, val, pos, left, middle, tree);
        else
            update((index << 1) + 2, val, pos, middle + 1, right, tree);

        tree[index] += val;
    }
}

int query(int index, int &left, int &right, int cLeft, int cRight, int tree[])
{
    if (left <= cLeft && right >= cRight)
        return tree[index];

    int sum = 0, middle = (cLeft + cRight) >> 1;
    if (middle >= left)
        sum += query((index << 1) + 1, left, right, cLeft, middle, tree);
    if (middle + 1 <= right)
        sum += query((index << 1) + 2, left, right, middle + 1, cRight, tree);

    return sum;
}

int nextInt(string &line, int &pos)
{
    if (pos < line.size())
    {
        int n = 0;
        while (line[pos] != ' ' && line[pos] != '\n')
            n = n * 10 + (line[pos++] - '0');
        pos++;
        return n;
    }

    return -1;
}

int main()
{
    int i, N, M, x;
    ifstream f("datorii.in");
    string line;
    getline(f, line, '~');
    line += ' ';
    f.close();

    int pos = 0;
    N = nextInt(line, pos);
    M = nextInt(line, pos);
    int length = (1 << ((int)log2(N) + 2)) - 1;
    int tree[length];
    fill(tree, tree + length, 0);
    for (i = 0; i < N; i++)
    {
        x = nextInt(line, pos);
        update(0, x, i, 0, N - 1, tree);
    }

    int op, y;
    ofstream g("datorii.out");
    for (i = 0 ; i < M; i++)
    {
        op = nextInt(line, pos);
        x = nextInt(line, pos);
        y = nextInt(line, pos);
        if (op == 0)
        {
            y *= -1;
            x--;
            update(0, y, x, 0, N - 1, tree);
        }
        else if (op == 1)
        {
            x--;
            y--;
            g << query(0, x, y, 0, N - 1, tree) << '\n';
        }
    }
    f.close();
    g.close();
    return 0;
}