Cod sursa(job #2951828)

Utilizator Chris_BlackBlaga Cristian Chris_Black Data 7 decembrie 2022 14:03:46
Problema Arbori indexati binar Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.2 kb
#include <fstream>
#define lsb(i) (i&(-i))
using namespace std;
ifstream cin("aib.in");
ofstream cout("aib.out");
const int N = 100009;
int n,m,x,cer,a,b;
unsigned long long aib[N];



void Update(int poz,int val)
{
    for(int i = poz; i<=n ; i += lsb(i))
        aib[i]+=val;
}
long long Sum(int poz)
{
    long long sum = 0;
    for(int i=poz; i>0 ; i -= lsb(i))
        sum += aib[i];
    return sum;
}

int Query(int val)
{
    int st = 1,dr = n, poz = 0;
    while(st<=dr)
    {
        int mij = (st+dr)>>1;
        if(Sum(mij) >= val)
        {
            poz = mij;
            dr = mij -1;
        }
        else
            st = mij +1;
    }
    if(Sum(poz) == val)return poz;
    else return -1;
}


int main()
{
    cin>>n>>m;
    for(int i=1;i<=n;++i)
        cin>>x,Update(i,x);
    for(int i=1;i<=m;++i)
    {
        cin>>cer;
        if(cer==0)
        {
            cin>>a>>b;
            Update(a,b);
        }
        else if(cer==1)
        {
            cin>>a>>b;
            cout<<Sum(b) - Sum(a-1)<<'\n';
        }
        else if(cer==2)
        {
            cin>>a;
            cout<<Query(a)<<'\n';
        }
    }
    return 0;
}