Cod sursa(job #3319881)

Utilizator Andrada_MincaAndrada Minca Andrada_Minca Data 3 noiembrie 2025 17:06:54
Problema Arbori indexati binar Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.33 kb
//
//  main.cpp
//  AIB
//
//  Created by Andrada Minca on 03.11.2025.
//

#include <fstream>
#include <vector>
using namespace std;
ifstream cin("aib.in");
ofstream cout("aib.out");
vector<long long> aib;
int lsb(int x)
{
    return (x&(-x));
}
void update(int x,int add)
{
    for(int i=x;i<aib.size();i+=lsb(i))
    {
        aib[i]+=add;
    }
}
long long query(int x)
{
    long long sum=0;
    for(int i=x;i>0;i-=lsb(i))
    {
        sum+=aib[i];
    }
    return sum;
}
int bs(long long s)
{
    int ans=0;
    long long sum=0;
    for(int pas=(1<<17);pas>0;pas/=2)
    {
        if(ans+pas+1<aib.size()&&sum+aib[ans+pas]<s)
        {
            ans+=pas;
            sum+=aib[ans];
        }
    }
    if(query(ans+1)==s)
    {
        return ans+1;
    }
    else return -1;
}
int main()
{
    int n,m;
    cin>>n>>m;
    aib.resize(n+1);
    for(int i=0;i<n;i++)
    {
        long long x;
        cin>>x;
        update(i+1,x);
    }
    for(int i=0;i<m;i++)
    {
        int c;
        cin>>c;
        if(c==1)
        {
            int a,b;
            cin>>a>>b;
            cout<<query(b)-query(a-1)<<"\n";
        }
        else if(c==0)
        {
            int a,b;
            cin>>a>>b;
            update(a,b);
        }
        else{
            int a;
            cin>>a;
            cout<<bs(a)<<'\n';
        }
    }
    return 0;
}