Cod sursa(job #3203705)

Utilizator gBneFlavius Andronic gBne Data 14 februarie 2024 11:36:36
Problema Arbori indexati binar Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.28 kb
#include <bits/stdc++.h>

using namespace std;

const int NMax = 100005;

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

int v[NMax], A[NMax], n;

void update(int a, int b){
    for(int i=a; i<=n; i += i & (-i)){
        A[i] += b;
    }
}

long long query(int a){
    long long sum = 0;
    for(int i=a; i>=1; i -= i & (-i)){
        sum += A[i];
    }
    return sum;
}

int cauta_pe_k(int a){
    int st = 1, dr = n;
    while(st <= dr){
        int mij = (st + dr) / 2;
        int val_gasita = query(mij);
        if(val_gasita == a){
            return mij;
        }
        else if(val_gasita < a){
            st = mij + 1;
        }
        else{
            dr = mij - 1;
        }
    }
    return -1;
}

int main()
{
    int m;
    fin >> n >> m;
    for(int i=1; i<=n; i++){
        fin >> v[i];
        update(i, v[i]);
    }
    int op, a, b;
    for(int i=1; i<=m; i++){
        fin >> op;
        if(op == 2){
            fin >> a;
            fout << cauta_pe_k(a) << '\n';
        }
        else{
            fin >> a >> b;
            if(op == 0){
                update(a, b);
            }
            else{
                fout << query(b) - query(a - 1) << '\n';
            }
        }
    }
    return 0;
}