10374: ARC085 —— F - NRE
[Creator : ]
Description
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.
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.
Input
Input is given from Standard Input in the following format:
```
$N$
$b_1$ $b_2$ $...$ $b_N$
$Q$
$l_1$ $r_1$
$l_2$ $r_2$
$:$
$l_Q$ $r_Q$
```
```
$N$
$b_1$ $b_2$ $...$ $b_N$
$Q$
$l_1$ $r_1$
$l_2$ $r_2$
$:$
$l_Q$ $r_Q$
```
Output
Print the minimum possible hamming distance.
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 $r_i \neq r_j$.
- $b$ 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 $r_i \neq r_j$.
Sample 1 Input
3
1 0 1
1
1 3
Sample 1 Output
1
Sample 2 Input
3
1 0 1
2
1 1
3 3
Sample 2 Output
0
Sample 3 Input
3
1 0 1
2
1 1
2 3
Sample 3 Output
1
5
0 1 0 1 0
1
1 5
2
Sample 4 Input
9
0 1 0 1 1 1 0 1 0
3
1 4
5 8
6 7
Sample 4 Output
3