Problem:
Range Add Query (RAQ)

Write a program which manipulates a sequence A = {a1, a2, . . . , an} with the following operations:

add(s, t, x): add x to as, as+1, ..., at.

get(i): output the value of ai.

Note that the initial values of ai (i = 1, 2, . . . , n) are 0.

Input

n q
query1
query2
:
queryq

In the first line, n (the number of elements in A) and q (the number of queries) are given. Then, ith query queryi is given in the following format:

0 s t x

or

1 t

The first digit represents the type of the query. '0' denotes add(s, t, x) and '1' denotes get(i).

Output

For each get operation, print the value.

Constraints

1 ≤ n ≤ 100000

1 ≤ q ≤ 100000

1 ≤ s ≤ t ≤ n

1 ≤ i ≤ n

0 ≤ x ≤ 1000

Sample Input 1

3 5
0 1 2 1
0 2 3 2
0 3 3 3
1 2
1 3

Sample Output 1

3
5

Sample Input 2

4 3
1 2
0 1 4 1
1 2

Sample Output 2

0
1

Solution in C# (judge verdict: Accepted)

using System.Text;
using System;

public class BIT
{
    private int[] data;
    public BIT(int n)
    {
        data = new int[n + 1];
    }
    public int getSum(int i)
    {
        var s = 0;
        while (i > 0)
        {
            s += data[i];
            i -= i & -i;
        }
        return s;
    }
    public void addix(int i, int x, int n)
    {
        while (i <= n)
        {
            data[i] += x;
            i += i & -i;
        }
    }
}

public class hello
{
    public static void Main()
    {
        string[] line = Console.ReadLine().Trim().Split(' ');
        var n = int.Parse(line[0]);
        var q = int.Parse(line[1]);
        getAns(n, q);
    }
    static void getAns(int n, int q)
    {
        var sb = new StringBuilder();
        var n2 = n + 2;
        var bit = new BIT(n2);
        for (int i = 0; i < q; i++)
        {
            string[] line = Console.ReadLine().Trim().Split(' ');
            if (line[0] == "0")
            {
                var s = int.Parse(line[1]);
                var t = int.Parse(line[2]);
                var x = int.Parse(line[3]);
                bit.addix(s, x, n2);
                bit.addix(t + 1, -x, n2);
            }
            else
            {
                var s = int.Parse(line[1]);
                var ans = bit.getSum(s);
                sb.Append(bit.getSum(s).ToString() + "\n");
            }
        }
        Console.Write(sb);
    }
}