Cod sursa(job #2760901)

Utilizator cezarinfoTulceanu Cezar cezarinfo Data 29 iunie 2021 14:58:09
Problema Arbori indexati binar Scor 100
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.23 kb
#include<cstdio>
using namespace std;
FILE*in=fopen("aib.in","r");
FILE*out=fopen("aib.out","w");
int n,m,c,a,b,aib[200005],i,po=1;
void up(int poz,int val)
{
    int pt=poz;
    while(pt<=po)
    {
        aib[pt]+=val;
        pt+=pt&(-pt);
    }
}
int sum(int poz)
{
    int pt=poz;
    int sol=0;
    while(pt>0)
    {
        sol+=aib[pt];
        pt-=pt&(-pt);
    }
    return sol;
}
int bs(int val)
{
    int pas=po;
    int ras=0;
    while(pas>0)
    {
        if(ras+pas<=n&&val==sum(ras+pas))
        {
            return ras+pas;
        }
        if(val>sum(ras+pas))
        {
            ras+=pas;
        }
        pas/=2;
    }
    return -1;
}
int main()
{
    fscanf(in,"%d%d",&n,&m);
    while(po<n)
    {
        po*=2;
    }
    for(i=1;i<=n;i++)
    {
        fscanf(in,"%d",&a);
        up(i,a);
    }
    for(i=1;i<=m;i++)
    {
        fscanf(in,"%d%d",&c,&a);
        if(c==0)
        {
            fscanf(in,"%d",&b);
            up(a,b);
        }
        else if(c==1)
        {
            fscanf(in,"%d",&b);
            fprintf(out,"%d\n",sum(b)-sum(a-1));
        }
        else
        {
            fprintf(out,"%d\n",bs(a));
        }
    }
}