Cod sursa(job #2846196)

Utilizator mihneazzzMacovei Daniel mihneazzz Data 8 februarie 2022 22:01:32
Problema Arbori indexati binar Scor 10
Compilator cpp-64 Status done
Runda Arhiva educationala Marime 1.27 kb
#include <bits/stdc++.h>
#define N 100005
using namespace std;
ifstream fin("aib.in");
ofstream fout("aib.out");
int a[N],n,m,aint[4*N],S;
void Update(int nod,int st,int dr,int x,int y)
{
    if(st==dr) aint[nod]=y;
    else
    {
        int mij=(st+dr)>>1;
        if(x<=mij) Update(2*nod,st,mij,x,y);
        else Update(2*nod+1,mij+1,dr,x,y);
        aint[nod]=aint[2*nod]+aint[2*nod+1];
    }
}
void Query(int nod,int st,int dr,int x,int y)
{
    if(x<=st && dr<=y) S+=aint[nod];
    else
    {
        int mij=(st+dr)>>1;
        if(x<=mij) Query(2*nod,st,mij,x,y);
        if(y>mij) Query(2*nod+1,mij+1,dr,x,y);
    }
}
int Search(int x)
{
    int st=1,dr=n,mij;
    while(st<=dr)
    {
        mij=(st+dr)>>1;
        S=0;
        Query(1,1,n,1,mij);
        if(S==x) return mij;
        else if(S<x) st=mij+1;
        else dr=mij-1;
    }
    return -1;
}
int main()
{
    int i,x,y,op;
    fin>>n>>m;
    for(i=1;i<=n;i++) fin>>a[i],Update(1,1,n,i,a[i]);
    while(m--)
    {
        fin>>op;
        if(op<2)
        {fin>>x>>y;
        if(!op) Update(1,1,n,x,a[x]+y);
        else S=0,Query(1,1,n,x,y),fout<<S<<"\n";}
        else
        {
            fin>>x;
            fout<<Search(x)<<"\n";
        }
    }
    return 0;
}