Cod sursa(job #1960064)

Utilizator DragosCDragos Corleanca DragosC Data 10 aprilie 2017 10:26:37
Problema Arbori indexati binar Scor 0
Compilator cpp Status done
Runda Arhiva educationala Marime 1.51 kb
#include <iostream>
#include <fstream>
#define zeros(x) ((x^(x-1))&x)
using namespace std;
int n,m;
int aib[100001];
void op0(int x, int q)
{
    for(int i=x; i<=n; i+=zeros(i))
        aib[i]+=q;
}
int Compute(int x)
{
    int sum=0;
    for(int i=x; i>0; i-=zeros(i))
        sum+=aib[i];
    return sum;
}
int op1(int a, int b)
{
    return Compute(b)-Compute(a-1);
}


int main()
{
    ifstream f("aib.in");
    ofstream g("aib.out");
    f>>n>>m;
    int x;
    for(int i=1; i<=n; i++)
    {
        f>>x;
        op0(i,x);
    }
    int y,z;
    for(int i=1; i<=m; i++)
    {
        f>>x;
        if(x==0)
        {
            f>>y>>z;
            op0(y,z);
        }
        else if(x==1)
        {
            f>>y>>z;
            g<<op1(y,z)<<'\n';
        }
        else
        {
            f>>y;
            int st=1,dr=n;
            while(st<=dr)
            {
                if(st==dr)
                {
                    if(Compute(st)==y)
                    {
                        g<<st<<'\n';
                        break;
                    }

                    else {g<<-1;break;}}
                    int mij=(st+dr)/2;
                    x=Compute(mij);
                    if(x==y)
                    {
                        g<<mij<<'\n';
                        break;
                    }
                    else if(x<y) st=mij+1;
                    else if(x>y) dr=mij-1;
            }
        }
    }
    return 0;
}