Cod sursa(job #3327712)

Utilizator SfichiAndreiSfichi Andrei SfichiAndrei Data 4 decembrie 2025 20:45:26
Problema Arbori indexati binar Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.31 kb
#include <iostream>
#include <bits/stdc++.h>
#define NMAX 100007
using namespace std;
ifstream fin ("aib.in");
ofstream fout ("aib.out");
int N,A[NMAX],M;
int tip,aib[NMAX];
int ub(int x)
{
    return (x&(-x));
}
void add(int x, int val)
{
    for(int i=x;i<=N;i+=ub(i))
        aib[i]+=val;
}
int SUM(int x)
{
    int s=0;
    for(int i=x;i>=1;i-=ub(i))
        s+=aib[i];
    return s;
}
int main()
{
    fin>>N>>M;
    for(int i=1;i<=N;i++)
        {
            fin>>A[i];
            add(i,A[i]);
        }
    while(M--)
    {
        fin>>tip;
        if(tip==0)
        {
            int a,b;
            fin>>a>>b;
            add(a,b);
        }
        if(tip==1)
        {
            int a,b;
            fin>>a>>b;
            fout<<SUM(b)-SUM(a-1)<<'\n';
        }
        if(tip==2)
        {
            int a,s=0,poz=0;
            fin>>a;
            for(int b=17;b>=0;b--)
            {
                if(poz+(1<<b)<=N && s+aib[poz+(1<<b)]<a)
                {
                    s+=aib[poz+(1<<b)];
                    poz+=(1<<b);
                }
            }
            if(poz+1>N || SUM(poz+1)!=a)
            {
                fout<<-1<<'\n';
            }
            else
                fout<<poz+1<<'\n';
        }
    }
    return 0;
}