Cod sursa(job #3358776)

Utilizator alex.iovita.23@gmail.comIovita Alexandru [email protected] Data 20 iunie 2026 10:58:58
Problema Arbori indexati binar Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.28 kb
#include<bits/stdc++.h>
#define int long long

using namespace std;

ifstream fin("aib.in");
ofstream fout("aib.out");

int n , q , tip , aib[100010];

inline void update(int x , int val){
    for(int i = x ; i <= n ; i += (i&(-i))) aib[i] += val;
}

inline int query(int x){
    int rez = 0;
    for(int i = x; i >= 1 ; i -= (i&(-i))) rez += aib[i];
    return rez;
}

signed main(){
    fin >> n >> q;
    for(int i = 1 ; i <= n ; i++){
        int x; fin >> x;
        update(i , x);
    }
    while(q--){
        fin >> tip;
        if(tip == 0){
            int a , b; fin >> a >> b;
            update(a , b);
        }
        else if(tip == 1){
            int a , b; fin >> a >> b;
            fout << query(b) - query(a - 1) << '\n';
        }
        else{
            int a; fin >> a;
            int st = 1 , dr = n , sol = 2e9;
            while(st <= dr){
                int mid = (st + dr) / 2;
                int x = query(mid);
                if(x == a){
                    sol = min(sol , mid);
                    dr = mid - 1;
                }
                else if(x < a) st = mid + 1;
                else dr = mid - 1;
            }
            if(sol == 2e9) sol = -1;
            fout << sol << '\n';
        }
    }
}