Cod sursa(job #1540528)

Utilizator cristibogdanPatrascu Cristian cristibogdan Data 2 decembrie 2015 21:37:01
Problema Arbori indexati binar Scor 100
Compilator cpp Status done
Runda Arhiva educationala Marime 1.12 kb
#include <fstream>

using namespace std;
ifstream f("aib.in");
ofstream g("aib.out");
int AIB[100011],n,m,i,x,tip,y;
void update(int poz, int c)
{
    int i;
    for(i=poz;i<=n; i+=(i&(-i)))
    {
        AIB[i]+=c;
    }
}
int query(int x)
{
    int i,val=0;
    for(i=x;i>0;i-=(i&(-i)))
    {
        val+=AIB[i];
    }
    return val;
}
int bin(int val)
{
    int i,k;
    for(k=1;k<n;k<<=1);
    for(i=0;k!=0;k>>= 1)
    {
        if(i+k<=n)
        {
            if(val >=AIB[i+k])
            {
                i+=k;
                val -= AIB[i];
                if(!val)
                    return i;
            }
        }
    }
    return -1;
}

int main()
{f>>n>>m;
    for(i=1;i<=n;i++){
        f>>x;
        update(i,x);}

    for(i=1;i<=m;i++){
        f>>tip;
        if(tip==0)
        {
            f>>x>>y;
            update(x,y);
        }
        else{
        if(tip==1)
        {
            f>>x>>y;
            g<<query(y)-query(x-1)<<'\n';
        }
        else{
            f>>x;
            g<<bin(x)<<'\n';
        }
    }
    }


    return 0;
}