Cod sursa(job #2573600)

Utilizator Groza_Iulia_DianaGroza Iulia Diana Groza_Iulia_Diana Data 5 martie 2020 18:19:15
Problema Arbori indexati binar Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.05 kb
#include <bits/stdc++.h>
#define nMax 100005

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

int n, m, x, tip, a, b, aib[nMax];

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

int sum(int pos)
{
    int s=0;
    for(int i=pos; i>=1; i-=(-i)&i)
        s+=aib[i];
    return s;
}

int src(int x)
{
    int l=1, r=n;
    while(l<=r)
    {
        int mid=(l+r)>>1;
        if(sum(mid)==x)
            return mid;
        if(sum(mid)>x)
            r=mid-1;
        else
            l=mid+1;
    }
    return -1;
}

int main()
{
    fin >> n >> m;
    for(int i=1; i<=n; i++)
    {
        fin >> x;
        update(x, i);
    }
    while(m--)
    {
        fin >> tip >> a;
        if(tip==0)
        {
            fin >> b;
            update(b, a);
        }
        else if(tip==1)
        {
            fin >> b;
            fout << sum(b)-sum(a-1) << "\n";
        }
        else
            fout << src(a) << "\n";
    }
    return 0;
}