Cod sursa(job #2350562)

Utilizator MateiAruxandeiMateiStefan MateiAruxandei Data 21 februarie 2019 15:28:20
Problema Arbori indexati binar Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.41 kb
#include <fstream>

#define endZero(x) ((x ^ (x - 1)) & x)
using namespace std;

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

int AIB[100005], n, m;

void Add(int poz, int val){
    for(int i = poz; i <= n; i += endZero(i))
        AIB[i] += val;
}

int Compute(int poz){
    int rez = 0;
    for(int i = poz; i > 0; i -= endZero(i))
        rez += AIB[i];
    return rez;
}

int main()
{
    fin >> n >> m;

    for(int i = 1; i <= n; ++i){
        int x;
        fin >> x;

        Add(i, x);
    }

    for(int i = 1; i <= m; ++i){
        int c;
        fin >> c;

        if(c == 0){
            int a, b;
            fin >> a >> b;

            Add(a, b);
        }
        else if(c == 1){
            int a, b;
            fin >> a >> b;
            fout << (Compute(b) - Compute(a - 1)) << '\n';
        }
        else {
            int a;
            fin >> a;

            int st = 1;
            int dr = n;
            int poz = -1;
            while(st <= dr){
                int mij = (st + dr) / 2;
                int val = Compute(mij);
                if(val == a){
                    poz = mij;
                    dr = mij - 1;
                }
                else if(val > a){
                    dr = mij - 1;
                }
                else st = mij + 1;
            }
            fout << poz << '\n';
        }
    }
    return 0;
}