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//Arbori indexati binar
#include<iostream>
#include<fstream>
#define nmax 100001
using namespace std;
int m,v[nmax];
int getParent(int index)
{
return index-(index & -index);
}
int getNext(int index)
{
return index+(index & -index);
}
void update(int BITree[],int n,int index,int val)
{
index++;
while(index<=n)
{
BITree[index]+=val;
index=getNext(index);
}
}
int *constructBITree(int arr[],int n)
{
int *BITree=new int[n+1];
for(int i=0;i<=n;i++)
BITree[i]=0;
//Arborele indexat binar are in plus nodul "dummy" 0, ca radacina (din constructia pe biti)
for(int i=0;i<n;i++)
update(BITree,n,i,arr[i]);
return BITree;
}
int getSum(int BITree[],int index)
{
int sum41=0;
//fan punk rock ?
++index;
//indexul din arbore este cu o unitate mai mare decat cel din vector4
while(index>0)
{
sum41+=BITree[index];
index=getParent(index);
}
return sum41;
}
int bs(int BITree[],int n,int st,int dr,int val)
{
//cout<<st<<' '<<dr<<' ';
if(dr<=0 || st>n) return -1;
else
{
int mid=(st+dr)>>1,x=getSum(BITree,mid-1);
if(x==val) return mid;
else
if(x<val)
bs(BITree,n,mid+1,dr,val);
else
bs(BITree,n,st,mid-1,val);
}
}
void read()
{
int n,i,c,a,b;
ifstream fin("aib.in");
ofstream fout("aib.out");
fin>>n>>m;
//v[0.....n-1]
//BITree[0.....n]
for(i=0;i<n;i++)
fin>>v[i];
int *BITree=constructBITree(v,n);
//cout<<getSum(BITree,4)<<' ';
for(i=1;i<=m;i++)
{
fin>>c;
if(!c)
{
fin>>a>>b;
update(BITree,n,a-1,b);
}
else
if(c==1)
{
fin>>a>>b;
//cout<<a<<b;
fout<<getSum(BITree,b-1)-getSum(BITree,a-2)<<'\n';
}
else
{
fin>>a;
//pozitia minima k astfel incat suma valorilor primilor k termeni sa fie exact a.
//numerele fiind naturale, elementele din getSum(BITree) sunt ordonate crescator
fout<<bs(BITree,n,1,n,a)<<'\n';
//for(i=0;i<=n;i++)
// cout<<BITree[i]<<' ';
// cout<<endl;
//cout<<"coapte!"<<'\n';
}
}
fin.close();
fout.close();
}
int main()
{
read();
}