Cod sursa(job #2509307)

Utilizator AlexDontuAlex Dontu AlexDontu Data 14 decembrie 2019 09:41:54
Problema Arbori indexati binar Scor 0
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 0.86 kb
#include <fstream>
#include <iostream>
#include <algorithm>
using namespace std;
ifstream fin ("aib.in");
ofstream fout ("aib.out");
int i,n,q,x,aib[100001],j,a,b,v[100001];
void update (int x,int p)
{
    for (int i=p; i<=n; i+=(i&(-i))) aib[i]+=x;
}
int sum (int p)
{
    int i,s=0;
    for (i=p; i>0; i-=(i&(-i)))
        s+=aib[i];
    return s;
}
int main()
{
    fin>>n>>q;
    for (i=1; i<=n; i++)
    {
        fin>>x;
        update(x,i);
        v[i]=x+v[i-1];
    }
    for (i=1; i<=q; i++)
    {
        fin>>x;
        if (x==0)
        {
            fin>>a>>b,update(b,a);
        }
        else if (x==1)
        {
            fin>>a>>b;
            fout<<sum(b)-sum(a-1)<<'\n';
        }
        else if (x==2)
        {
            fin>>a,fout<<upper_bound(v+1,v+n+1,a)-v-1<<'\n';
        }
    }

    return 0;
}