Cod sursa(job #2549951)

Utilizator Catalin_GriuGriu Catalin Catalin_Griu Data 18 februarie 2020 09:43:08
Problema Arbori indexati binar Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.54 kb
#include <bits/stdc++.h>
#define ll long long
#define pii pair<int, int>
#define pll pair<ll, ll>
#define NMAX 100005
using namespace std;
ifstream fin("aib.in");
ofstream fout("aib.out");

int n, m, x, y, q;
int aib[NMAX];


int last2( int i )
{
    return i&-i;
}
void update(int pos, int val)
{
    for(int i=pos; i<=n; i+=last2(i))
        aib[i]+=val;
}

int query(int pos)
{
    int sum= 0;

    for(int i=pos; i>0; i-=last2(i))
    {
        sum+=aib[i];
    }
    return sum;
}

int main()
{
    fin>>n>>m;
    for(int i=1; i<=n; i++)
    {
        fin>>x;
        update(i, x);
    }
    for(int i=1; i<=m; i++)
    {
        fin>>q;
        if(q==1)
        {
            fin>>x>>y;
            int s1 = query(x-1);
            int s2 = query(y);
            fout<<s2-s1<<'\n';
        }
        else if(q==0)
        {
            fin>>x>>y;
            update(x, y);
        }
        else{
            fin>>x;
            int k, o, p2;
            p2==1;
             for (p2 = 1; p2 <=n; p2 <<= 1);
            for(o=1; p2 ; p2>>=1)
            {
                if(o+p2<=n)
                {
                    k = query(o+p2);
                   // cout<<k<<' '<<o+p2<<'\n';
                    if(k<=x)
                        o+=p2;
                }

            }

            if(query(o)==x)
                fout<<o<<'\n';
            else
            {
               // cout<<i<<' '<<o<<'\n';
                fout<<-1<<'\n';
            }
        }
    }

    return 0;
}