Cod sursa(job #3160343)

Utilizator gabriel.9619Gabriel Stefan Tita gabriel.9619 Data 23 octombrie 2023 19:02:33
Problema Arbori indexati binar Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.22 kb
#include <fstream>
using namespace std;
ifstream fin("aib.in");
ofstream fout("aib.out");

int v[100010], a[100011];
int n, m;

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

int query(int poz)
{
    int s=0;
    for(int i=poz;i>0;i-=(i&-i))
    {
        s+=a[i];
    }
    return s;
}

int cautbin(int k)
{
    int st=1, dr=n;
    while(st<=dr)
    {
        int mid=(st+dr)/2;
        int crt=query(mid);
        if(crt>k)
        {
            dr=mid-1;
        }
        else
        if(crt==k)
        {
            return mid;
        }
        else
        {
            st=mid+1;
        }
    }
    return -1;
}

int main()
{
    int i, t, poz, val, a, b, k;
    fin>>n>>m;
    for(i=1;i<=n;i++)
    {
        fin>>v[i];
        update(i, v[i]);
    }
    for(i=1;i<=m;i++)
    {
        fin>>t;
        if(t==0)
        {
            fin>>poz>>val;
            update(poz, val);
        }
        else
        if(t==1)
        {
            fin>>a>>b;
            fout<<query(b)-query(a-1)<<"\n";
        }
        else
        {
            fin>>k;
            fout<<cautbin(k)<<"\n";
        }
    }
}