Cod sursa(job #3285176)

Utilizator TimurealTimu Ionut Timureal Data 12 martie 2025 16:28:47
Problema Arbori indexati binar Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.27 kb
#include <bits/stdc++.h>
#define cin fin
#define cout fout
using namespace std;
ifstream fin("aib.in");
ofstream fout("aib.out");
int BIT[100005] , n , q;
void update(int val , int poz){
    for(int i=poz ; i<=n ; i+=(i&(-i))){
        BIT[i]+=val;
    }
}
int query(int poz){
    int sol=0;
    for(int i=poz ; i>0 ; i-=(i&(-i))){
        sol+=BIT[i];
    }
    return sol;
}

int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);
    cin>>n>>q;
    for(int i=1 ; i<=n; i++)
    {
        int aux;
        cin>>aux;
        update(aux , i);
    }
    while(q--){
        int op ,a  ,b;
        cin>>op;
        if(op==0){
            cin>>a>>b;
            update(b , a);
        }
        if(op==1){
            cin>>a>>b;
            cout<<query(b)-query(a-1)<<"\n";
        }
        if(op==2){
            cin>>a;
            int st=1 , dr=n , adv=-1;
            while(st<=dr){
                int mid=(st+dr)/2;
                if(query(mid)>=a){
                    adv=mid;
                    dr=mid-1;
                }
                else{
                    st=mid+1;
                }
            }
            cout<<((query(adv)==a) ? adv : -1);
            cout<<"\n";
        }
    }
    return 0;
}