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#include <iostream>
#include <fstream>
#define DM 100005
using namespace std;
ifstream fin("aib.in");
ofstream fout("aib.out");
int aib[DM], n, m, x, a, b;
void update(int pos, int val)
{
for(; pos <= n; pos += (pos & (-pos)))
aib[pos] += val;
}
int sum(int pos)
{
int rez = 0;
for(; pos > 0; pos -= (pos & (-pos)))
rez += aib[pos];
return rez;
}
int query(int a, int b)
{
return (sum(b) - sum(a - 1));
}
int caut_bin(int val) // O(log^2 n)
{
int st = 0, dr = n + 1, mij;
while(dr - st > 1)
{
int mij = (st + dr) / 2;
if(val > sum(mij))
st = mij;
else dr = mij;
}
if(sum(dr) == val)
return dr;
return -1;
}
int caut_bin_Patrascu(int val) // O(log n) - dubioasa
{
int pos = 0, step = 1, aux = val;
for(; step <= n; step <<= 1) ;
for(; step > 0; step >>= 1)
if(pos + step <= n)
if(aib[pos + step] < val)
{
pos += step;
val -= aib[pos];
}
pos++;
if(sum(pos) == aux)
return pos;
return -1;
}
int main()
{
fin >> n >> m;
for(int i = 1; i <= n; i++)
{
fin >> x;
update(i, x);
}
for(int i = 1; i <= m; i++)
{
fin >> x;
if(x == 0)
{
fin >> a >> b;
update(a, b);
}
if(x == 1)
{
fin >> a >> b;
fout << query(a, b) << '\n';
}
if(x == 2)
{
fin >> a;
fout << caut_bin_Patrascu(a) << '\n';
}
}
return 0;
}