Problem:
Score : 100 points

Problem Statement

You are given an array a_0, a_1, ..., a_{N-1} of length N. Process Q queries of the following types.

0 p x: a_p \gets a_p + x

1 l r: Print \sum_{i = l}^{r - 1}{a_i}.

Constraints

1 \leq N, Q \leq 500,000

0 \leq a_i, x \leq 10^9

0 \leq p < N

0 \leq l_i < r_i \leq N

All values in Input are integer.

Input

Input is given from Standard Input in the following format:

N Q
a_0 a_1 ... a_{N - 1}
\textrm{Query}_0
\textrm{Query}_1
:
\textrm{Query}_{Q - 1}

Output

For each query of the latter type, print the answer.

Sample Input 1

5 5
1 2 3 4 5
1 0 5
1 2 4
0 3 10
1 0 5
1 0 3

Sample Output 1

15
7
25
6

Solution in Ruby (2.7.1) (judge verdict: Accepted)

class FenwickTree
    def initialize(n)
        @data = Array.new(n){0}
    end
    def add(i, x)
        i += 1
        while i <= @data.size
            @data[i - 1] += x
            i += i & -i
        end
    end
    def sum(r)
        s = 0
        while r > 0
            s += @data[r - 1]
            r -= r & -r
        end
        s
    end
end 

N,Q=gets.split.map(&:to_i)
ft=FenwickTree.new(N)
A=gets.split.map(&:to_i)
N.times{|i|
	ft.add(i, A[i])
}
Q.times{
	q,a,b=gets.split.map(&:to_i)
	case q
	when 0
		ft.add(a, b)
	when 1
		puts ft.sum(b)-ft.sum(a)
	end
}