Cod sursa(job #3127848)

Utilizator andystarzSuna Andrei andystarz Data 7 mai 2023 21:21:22
Problema Arbori indexati binar Scor 0
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.24 kb
#include <fstream>

using namespace std;

ifstream cin("aib.in");
ofstream cout("aib.out");

long long v[100005];
void update(long long poz, long long a, long long n)
{
    for (long long i=poz; i<=n; i+=(i&-i))
    {
        v[i]+=a;
    }
    return;
}
long long long long query(long long poz)
{
    long long s=0;
    for (long long i=poz; i>0; i-=(i&-i))
    {
        s+=v[i];
    }
    return s;
}
long long bsaintb(long long k, long long n)
{
    long long poz=0,s=0;
    long long pas=1<<20;
    while (pas>0)
    {
        if ((poz+pas)<=n && s+v[poz+pas]<=k)
            poz+=pas,s+=v[poz];
        pas/=2;
    }
    if (s   k)
        return -1;
    else
        return poz;
}
int main()
{
    long long n, q, a, cer, b;
    cin>>n>>q;
    for (long long i=1; i<=n; i++)
    {
        cin>>a;
        update(i, a, n);
    }
    for (long long i=0; i<q; i++)
    {
        cin>>cer;
        if (cer==0)
        {
            cin>>a>>b;
            update(a, b, n);
        }
        else if (cer==1)
        {
            cin>>a>>b;
            cout<<query(b)-query(a-1)<<'\n';
        }
        else
        {
            cin>>a;
            cout<<bsaintb(a, n)<<'\n';
        }
    }
}