Cod sursa(job #2387886)
Utilizator | Data | 25 martie 2019 12:44:35 | |
---|---|---|---|
Problema | Arbori indexati binar | Scor | 100 |
Compilator | cpp-64 | Status | done |
Runda | Arhiva educationala | Marime | 1.8 kb |
#include <fstream>
using namespace std;
ifstream cin("aib.in");
ofstream cout("aib.out");
const int N=100000+7;
int n,m;
int aib[N];
void add(int p,int x)
{
for(int i=p;i<=n;i+=i&(-i))
{
aib[i]+=x;
}
}
int get(int p)
{
int r=0;
for(int i=p;i>=1;i-=i&(-i))
{
r+=aib[i];
}
return r;
}
int main()
{
cin>>n>>m;
for(int i=1;i<=n;i++)
{
int x;
cin>>x;
add(i,x);
}
while(m--)
{
int t,x;
cin>>t>>x;
if(t==0)
{
int y;
cin>>y;
add(x,y);
}
if(t==1)
{
int y;
cin>>y;
cout<<get(y)-get(x-1)<<"\n";
}
if(t==2)
{
int r=0,pas=(1<<17),cur=0;
while(pas)
{
if(r+pas<=n && cur+aib[r+pas]<x)
{
r+=pas;
cur+=aib[r];
}
pas>>=1;
}
r++;
if(r<=n && get(r)==x)
{
cout<<r<<"\n";
}
else
{
cout<<"-1\n";
}
}
}
return 0;
}