Cod sursa(job #1650324)

Utilizator killlerr1Chilom Mircea killlerr1 Data 11 martie 2016 17:42:09
Problema Datorii Scor 100
Compilator cpp Status done
Runda Arhiva de probleme Marime 1.31 kb
#include <fstream>
using namespace std;

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

const int MAXN = 15001;

int arb[4*MAXN];
int n, m, a, b, pos, val;
int suma;


void Update(int nod, int l, int r);
void Query(int nod, int l, int r);

int main()
{
    is >> n >> m;
    for( int i = 1; i <= n; ++i )
    {
        is >> a;
        pos = i;
        val = a * -1;
        Update(1, 1, n);
    }

    int op;

    for( int i = 1; i <= m; ++i )
    {
        is >> op >> a >> b;
        if( op == 0 )
        {
            pos = a;
            val = b;
            Update(1, 1, n);
        }
        else
        {
            suma = 0;
            Query(1, 1, n);
            os << suma << '\n';
        }
    }

}

void Update(int nod, int l, int r)
{
    if( l == r )
    {
        arb[nod] -= val;
        return;
    }

    int mid = (l+r) / 2;
    if( pos <= mid )
        Update(2 * nod, l, mid);
    else
        Update(2*nod + 1, mid+1, r);

    arb[nod] = arb[nod*2] + arb[nod*2+1];
}

void Query(int nod, int l, int r)
{
    if( l >= a && r <= b )
    {
        suma += arb[nod];
        return;
    }
    int mid = (l+r) / 2;
    if( a <= mid )
        Query(2*nod, l, mid);
    if( mid < b )
        Query(2*nod+1, mid+1, r);
}