Cod sursa(job #1668206)

Utilizator ticozaurStratila Andrei ticozaur Data 29 martie 2016 17:14:43
Problema Arbori indexati binar Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.29 kb
#include <iostream>
#include <fstream>
using namespace std;
#define zeros(x) ((x^(x-1))&x)
ifstream fin("aib.in");
ofstream fout("aib.out");
int abi[100001],n,m,x,t;
void adauga(int ind,int val)
{
    for(int i=ind; i<=n; i+=zeros(i))
        abi[i]+=val;
}

int sum(int ind)
{
    int s=0;
    for(int i=ind; i>0; i-=zeros(i))
        s=s+abi[i];
    return s;
}
int query(int a)
{
    int st=1,dr=n;
    int mij=(st+dr)/2;
    int valo=sum(mij);
    while(valo!=a && st<=dr)
    {
        if(a<valo)
        {
            dr=mij-1;
        }
        else
        {
            st=mij+1;
        }
        mij=(st+dr)/2;
        valo=sum(mij);
    }
    if(st<=dr)
    {
        return mij;
    }
    else
    {
        return -1;
    }
}
int main()
{
    fin>>n>>m;
    int i,ind,val,st,dr;
    for(i=1; i<=n; i++)
    {
        fin>>x;
        adauga(i,x);
    }

    for(i=1; i<=m; i++)
    {
        fin>>t;
        if(t==0)
        {
            fin>>ind>>val;
            adauga(ind,val);
        }
        else if(t==1)
        {
            fin>>st>>dr;
            fout<<sum(dr)-sum(st-1)<<'\n';
        }
        else if(t==2)
        {
            fin>>val;
            fout<<query(val)<<'\n';
        }

    }
    return 0;
}