Cod sursa(job #3258933)

Utilizator AlexanderCernyCernaianu Alexandru AlexanderCerny Data 24 noiembrie 2024 12:53:03
Problema Arbori indexati binar Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.18 kb
#include <fstream>
#define DIM 100001

using namespace std;

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

int n,m,i,j,x,op;
int aib[DIM];
int a,b;
void update(int poz, int val)
{
    for(int i=poz;i<=n;i+=(i&-i))
        aib[i]+=val;
}
int query(int poz)
{
    int sum=0;
    for(int i=poz;i>=1;i-=(i&-i))
        sum+=aib[i];
    return sum;
}
int cb(int x)
{
    int st=1, dr=n;
    int poz=-1;
    while(st<=dr)
    {
        int mid=(st+dr)/2;
        int s=query(mid);
        if(s==x)
        {
            poz=mid;
            dr=mid-1;
        }
        else
            if(s>x)
                dr=mid-1;
            else
                st=mid+1;
    }
    return poz;
}
int main()
{
    fin>>n>>m;
    for(i=1;i<=n;i++)
    {
        fin>>x;
        update(i, x);
    }
    for(i=1;i<=m;i++)
    {
        fin>>op;
        if(op==0)
        {
            fin>>a>>b;
            update(a,b);
        }
        else if(op==1)
        {
            fin>>a>>b;
            fout<<query(b)-query(a-1)<<'\n';
        }
        else
        {
            fin>>a;
            fout<<cb(a)<<'\n';
        }
    }
    return 0;
}