Cod sursa(job #3193757)

Utilizator proflaurianPanaete Adrian proflaurian Data 15 ianuarie 2024 17:05:06
Problema Arbori indexati binar Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.17 kb
#include <bits/stdc++.h>

using namespace std;
ifstream f("aib.in");
ofstream g("aib.out");
const int N = 100001;
int n,m,aib[N];
int suma(int p)
{
    int ret=0;
    for(int i=p;i>0;i-=i&(-i))
        ret+=aib[i];
    return ret;
}
void aduna(int p,int val)
{
    for(int i=p;i<=n;i+=i&(-i))
        aib[i]+=val;
}
int main()
{
    f>>n>>m;
    for(int i=1;i<=n;i++)
    {
        int x;
        f>>x;
        aduna(i,x);
    }
    for(int i=1;i<=m;i++)
    {
        int tip;
        f>>tip;
        if(tip==0)
        {
            int poz,val;
            f>>poz>>val;
            aduna(poz,val);
        }
        else if(tip==1)
        {
            int st,dr;
            f>>st>>dr;
            g<<suma(dr)-suma(st-1)<<'\n';
        }
        else
        {
            int k;
            f>>k;
            int lo=0,hi=n,mi;
            while(hi-lo>1)
            {
                mi=(lo+hi)/2;
                if(suma(mi)<k)
                    lo=mi;
                else
                    hi=mi;
            }
            if(suma(hi)!=k)
                hi=-1;
            g<<hi<<'\n';
        }

    }
    return 0;
}