You are given a sequence a = {a_1, ..., a_N} with all zeros, and a sequence b = {b_1, ..., b_N} consisting of 0 and 1. The length of both is N.
You can perform Q kinds of operations. The i-th operation is as follows:
- Replace each of a_{l_i}, a_{l_i + 1}, ..., a_{r_i} with 1.
Minimize the hamming distance between a and b, that is, the number of i such that $a_i \neq b_i$, by performing some of the Q operations.

-----Constraints-----
- $1 \leq N \leq 200,000$
- b consists of 0 and 1.
- $1 \leq Q \leq 200,000$
- $1 \leq l_i \leq r_i \leq N$
- If $i \neq j, either l_i \neq l_j$ or $r_i \neq r_j$.

-----Input-----
Input is given from Standard Input in the following format:
N
b_1 b_2 ... b_N
Q
l_1 r_1
l_2 r_2
:
l_Q r_Q

-----Output-----
Print the minimum possible hamming distance.

-----Sample Input-----
3
1 0 1
1
1 3

-----Sample Output-----
1

If you choose to perform the operation, a will become {1, 1, 1}, for a hamming distance of 1.

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