Cod sursa(job #2349900)

Utilizator radurotaruRotaru Radu Stefan radurotaru Data 20 februarie 2019 20:24:35
Problema Arbori indexati binar Scor 0
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.01 kb
#include <fstream>

using namespace std;

ifstream f("aib.in");
ofstream g("aib.out");

int BITree[100005],v[100005],n,x,m,a,b;

int getSum(int q)
{
    int s=0;
    while(q)
    {
        s=s+BITree[q];
        q-=q &(-q);
    }
    return s;
}

void update(int q, int val)
{
    while(q<= n)
    {
        BITree[q]+=val;
        q+=q &(-q);
    }
}

int main()
{
    f>>n>>m;
    for(int i=1; i<=n; i++)
    {
        f>>v[i];
        update(i, v[i]);
    }

    for(int i=1; i<=m; i++)
    {
        f>>x;
        if(x==0)
        {
            f>>a>>b;
            update(a, b);
        }
        if(x==1)
        {
            f>>a>>b;
            g<<getSum(b)-getSum(a-1)<<'\n';
        }
        if(x==2)
        {
            f>>a;
            for(int i=1; i<=n; i++)
            {
                if(getSum(i)==a)
                {
                    g<<i<<'\n';
                    break;
                }
            }
        }
    }
    return 0;
}