#D9353. Divide Powers
Divide Powers
Divide Powers
You are given a multiset of powers of two. More precisely, for each i from 0 to n exclusive you have cnt_i elements equal to 2^i.
In one operation, you can choose any one element 2^l > 1 and divide it into two elements 2^{l - 1}.
You should perform q queries. Each query has one of two types:
- "1 pos val" — assign cnt_{pos} := val;
- "2 x k" — calculate the minimum number of operations you need to make at least k elements with value lower or equal to 2^x.
Note that all queries of the second type don't change the multiset; that is, you just calculate the minimum number of operations, you don't perform them.
Input
The first line contains two integers n and q (1 ≤ n ≤ 30; 1 ≤ q ≤ 2 ⋅ 10^5) — the size of array cnt and the number of queries.
The second line contains n integers cnt_0, cnt_1, ..., cnt_{n - 1} (0 ≤ cnt_i ≤ 10^6).
Next q lines contain queries: one per line. Each query has one of two types:
- "1 pos val" (0 ≤ pos < n; 0 ≤ val ≤ 10^6);
- "2 x k" (0 ≤ x < n; 1 ≤ k ≤ 10^{15}).
It's guaranteed that there is at least one query of the second type.
Output
For each query of the second type, print the minimum number of operations you need to make at least k elements with a value lower or equal to 2^x or -1 if there is no way to do it.
Example
Input
6 11 0 1 0 0 1 0 2 1 5 2 4 18 1 1 0 2 2 5 2 0 17 1 0 3 2 1 2 1 1 4 1 4 0 1 5 1 2 2 8
Output
4 16 4 -1 0 1
inputFormat
Input
The first line contains two integers n and q (1 ≤ n ≤ 30; 1 ≤ q ≤ 2 ⋅ 10^5) — the size of array cnt and the number of queries.
The second line contains n integers cnt_0, cnt_1, ..., cnt_{n - 1} (0 ≤ cnt_i ≤ 10^6).
Next q lines contain queries: one per line. Each query has one of two types:
- "1 pos val" (0 ≤ pos < n; 0 ≤ val ≤ 10^6);
- "2 x k" (0 ≤ x < n; 1 ≤ k ≤ 10^{15}).
It's guaranteed that there is at least one query of the second type.
outputFormat
Output
For each query of the second type, print the minimum number of operations you need to make at least k elements with a value lower or equal to 2^x or -1 if there is no way to do it.
Example
Input
6 11 0 1 0 0 1 0 2 1 5 2 4 18 1 1 0 2 2 5 2 0 17 1 0 3 2 1 2 1 1 4 1 4 0 1 5 1 2 2 8
Output
4 16 4 -1 0 1
样例
6 11
0 1 0 0 1 0
2 1 5
2 4 18
1 1 0
2 2 5
2 0 17
1 0 3
2 1 2
1 1 4
1 4 0
1 5 1
2 2 8
4
16
4
-1
0
1
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