apaz/codeforces-genesys huggingface dataset:
You are an expert competitive programmer. You will be given a problem statement, test case constraints and example test inputs and outputs. Please reason step by step about the solution (that must respect memory and time limits), then provide a complete implementation in c++17.

Your solution must read input from standard input (cin), write output to standard output (cout).
Do not include any debug prints or additional output.

Put your final solution within a single code block:
```cpp
<your code here>
```

Execution time limit: 1.0 seconds
Memory limit: 256.0 MB

# Problem
A permutation of length $$$n$$$ is a sequence of integers from $$$1$$$ to $$$n$$$ of length $$$n$$$ containing each number exactly once. For example, $$$[1]$$$, $$$[4, 3, 5, 1, 2]$$$, $$$[3, 2, 1]$$$ are permutations, and $$$[1, 1]$$$, $$$[0, 1]$$$, $$$[2, 2, 1, 4]$$$ are not.

There was a permutation $$$p[1 \dots n]$$$. It was merged with itself. In other words, let's take two instances of $$$p$$$ and insert elements of the second $$$p$$$ into the first maintaining relative order of elements. The result is a sequence of the length $$$2n$$$.

For example, if $$$p=[3, 1, 2]$$$ some possible results are: $$$[3, 1, 2, 3, 1, 2]$$$, $$$[3, 3, 1, 1, 2, 2]$$$, $$$[3, 1, 3, 1, 2, 2]$$$. The following sequences are not possible results of a merging: $$$[1, 3, 2, 1, 2, 3$$$], [$$$3, 1, 2, 3, 2, 1]$$$, $$$[3, 3, 1, 2, 2, 1]$$$.

For example, if $$$p=[2, 1]$$$ the possible results are: $$$[2, 2, 1, 1]$$$, $$$[2, 1, 2, 1]$$$. The following sequences are not possible results of a merging: $$$[1, 1, 2, 2$$$], [$$$2, 1, 1, 2]$$$, $$$[1, 2, 2, 1]$$$.

Your task is to restore the permutation $$$p$$$ by the given resulting sequence $$$a$$$. It is guaranteed that the answer exists and is unique.

You have to answer $$$t$$$ independent test cases.

## Input Format
The first line of the input contains one integer $$$t$$$ ($$$1 \le t \le 400$$$) — the number of test cases. Then $$$t$$$ test cases follow.

The first line of the test case contains one integer $$$n$$$ ($$$1 \le n \le 50$$$) — the length of permutation. The second line of the test case contains $$$2n$$$ integers $$$a_1, a_2, \dots, a_{2n}$$$ ($$$1 \le a_i \le n$$$), where $$$a_i$$$ is the $$$i$$$-th element of $$$a$$$. It is guaranteed that the array $$$a$$$ represents the result of merging of some permutation $$$p$$$ with the same permutation $$$p$$$.

## Output Format
For each test case, print the answer: $$$n$$$ integers $$$p_1, p_2, \dots, p_n$$$ ($$$1 \le p_i \le n$$$), representing the initial permutation. It is guaranteed that the answer exists and is unique.

## Examples
```input
5
2
1 1 2 2
4
1 3 1 4 3 4 2 2
5
1 2 1 2 3 4 3 5 4 5
3
1 2 3 1 2 3
4
2 3 2 4 1 3 4 1
```
```output
1 2 
1 3 4 2 
1 2 3 4 5 
1 2 3 
2 3 4 1
```

Now solve the problem and return the code.
You are an expert competitive programmer. You will be given a problem statement, test case constraints and example test inputs and outputs. Please reason step by step about the solution (that must respect memory and time limits), then provide a complete implementation in c++17.

Your solution must read input from standard input (cin), write output to standard output (cout).
Do not include any debug prints or additional output.

Put your final solution within a single code block:
```cpp
<your code here>
```

Execution time limit: 3.0 seconds
Memory limit: 256.0 MB

# Problem
You are given a graph consisting of $$$n$$$ vertices and $$$m$$$ edges. It is not guaranteed that the given graph is connected. Some edges are already directed and you can't change their direction. Other edges are undirected and you have to choose some direction for all these edges.

You have to direct undirected edges in such a way that the resulting graph is directed and acyclic (i.e. the graph with all edges directed and having no directed cycles). Note that you have to direct all undirected edges.

You have to answer $$$t$$$ independent test cases.

## Input Format
The first line of the input contains one integer $$$t$$$ ($$$1 \le t \le 2 \cdot 10^4$$$) — the number of test cases. Then $$$t$$$ test cases follow.

The first line of the test case contains two integers $$$n$$$ and $$$m$$$ ($$$2 \le n \le 2 \cdot 10^5$$$, $$$1 \le m \le min(2 \cdot 10^5, \frac{n(n-1)}{2})$$$) — the number of vertices and the number of edges in the graph, respectively.

The next $$$m$$$ lines describe edges of the graph. The $$$i$$$-th edge is described with three integers $$$t_i$$$, $$$x_i$$$ and $$$y_i$$$ ($$$t_i \in [0; 1]$$$, $$$1 \le x_i, y_i \le n$$$) — the type of the edge ($$$t_i = 0$$$ if the edge is undirected and $$$t_i = 1$$$ if the edge is directed) and vertices this edge connects (the undirected edge connects vertices $$$x_i$$$ and $$$y_i$$$ and directed edge is going from the vertex $$$x_i$$$ to the vertex $$$y_i$$$). It is guaranteed that the graph do not contain self-loops (i.e. edges from the vertex to itself) and multiple edges (i.e. for each pair ($$$x_i, y_i$$$) there are no other pairs ($$$x_i, y_i$$$) or ($$$y_i, x_i$$$)).

It is guaranteed that both sum $$$n$$$ and sum $$$m$$$ do not exceed $$$2 \cdot 10^5$$$ ($$$\sum n \le 2 \cdot 10^5$$$; $$$\sum m \le 2 \cdot 10^5$$$).

## Output Format
For each test case print the answer — "NO" if it is impossible to direct undirected edges in such a way that the resulting graph is directed and acyclic, otherwise print "YES" on the first line and $$$m$$$ lines describing edges of the resulted directed acyclic graph (in any order). Note that you cannot change the direction of the already directed edges. If there are several answers, you can print any.

## Examples
```input
4
3 1
0 1 3
5 5
0 2 1
1 1 5
1 5 4
0 5 2
1 3 5
4 5
1 1 2
0 4 3
1 3 1
0 2 3
1 2 4
4 5
1 4 1
1 1 3
0 1 2
1 2 4
1 3 2
```
```output
YES
3 1
YES
2 1
1 5
5 4
2 5
3 5
YES
1 2
3 4
3 1
3 2
2 4
NO
```

## Note
Explanation of the second test case of the example:

Explanation of the third test case of the example:

Now solve the problem and return the code.
You are an expert competitive programmer. You will be given a problem statement, test case constraints and example test inputs and outputs. Please reason step by step about the solution (that must respect memory and time limits), then provide a complete implementation in c++17.

Your solution must read input from standard input (cin), write output to standard output (cout).
Do not include any debug prints or additional output.

Put your final solution within a single code block:
```cpp
<your code here>
```

Execution time limit: 2.0 seconds
Memory limit: 256.0 MB

# Problem
You are given a tree (connected graph without cycles) consisting of $$$n$$$ vertices. The tree is unrooted — it is just a connected undirected graph without cycles.

In one move, you can choose exactly $$$k$$$ leaves (leaf is such a vertex that is connected to only one another vertex) connected to the same vertex and remove them with edges incident to them. I.e. you choose such leaves $$$u_1, u_2, \dots, u_k$$$ that there are edges $$$(u_1, v)$$$, $$$(u_2, v)$$$, $$$\dots$$$, $$$(u_k, v)$$$ and remove these leaves and these edges.

Your task is to find the maximum number of moves you can perform if you remove leaves optimally.

You have to answer $$$t$$$ independent test cases.

## Input Format
The first line of the input contains one integer $$$t$$$ ($$$1 \le t \le 2 \cdot 10^4$$$) — the number of test cases. Then $$$t$$$ test cases follow.

The first line of the test case contains two integers $$$n$$$ and $$$k$$$ ($$$2 \le n \le 2 \cdot 10^5$$$; $$$1 \le k < n$$$) — the number of vertices in the tree and the number of leaves you remove in one move, respectively. The next $$$n-1$$$ lines describe edges. The $$$i$$$-th edge is represented as two integers $$$x_i$$$ and $$$y_i$$$ ($$$1 \le x_i, y_i \le n$$$), where $$$x_i$$$ and $$$y_i$$$ are vertices the $$$i$$$-th edge connects. It is guaranteed that the given set of edges forms a tree.

It is guaranteed that the sum of $$$n$$$ does not exceed $$$2 \cdot 10^5$$$ ($$$\sum n \le 2 \cdot 10^5$$$).

## Output Format
For each test case, print the answer — the maximum number of moves you can perform if you remove leaves optimally.

## Examples
```input
4
8 3
1 2
1 5
7 6
6 8
3 1
6 4
6 1
10 3
1 2
1 10
2 3
1 5
1 6
2 4
7 10
10 9
8 10
7 2
3 1
4 5
3 6
7 4
1 2
1 4
5 1
1 2
2 3
4 3
5 3
```
```output
2
3
3
4
```

## Note
The picture corresponding to the first test case of the example:

There you can remove vertices $$$2$$$, $$$5$$$ and $$$3$$$ during the first move and vertices $$$1$$$, $$$7$$$ and $$$4$$$ during the second move.

The picture corresponding to the second test case of the example:

There you can remove vertices $$$7$$$, $$$8$$$ and $$$9$$$ during the first move, then vertices $$$5$$$, $$$6$$$ and $$$10$$$ during the second move and vertices $$$1$$$, $$$3$$$ and $$$4$$$ during the third move.

The picture corresponding to the third test case of the example:

There you can remove vertices $$$5$$$ and $$$7$$$ during the first move, then vertices $$$2$$$ and $$$4$$$ during the second move and vertices $$$1$$$ and $$$6$$$ during the third move.

Now solve the problem and return the code.
You are an expert competitive programmer. You will be given a problem statement, test case constraints and example test inputs and outputs. Please reason step by step about the solution (that must respect memory and time limits), then provide a complete implementation in c++17.

Your solution must read input from standard input (cin), write output to standard output (cout).
Do not include any debug prints or additional output.

Put your final solution within a single code block:
```cpp
<your code here>
```

Execution time limit: 1.0 seconds
Memory limit: 256.0 MB

# Problem
You are given the array $$$a$$$ consisting of $$$n$$$ positive (greater than zero) integers.

In one move, you can choose two indices $$$i$$$ and $$$j$$$ ($$$i \ne j$$$) such that the absolute difference between $$$a_i$$$ and $$$a_j$$$ is no more than one ($$$|a_i - a_j| \le 1$$$) and remove the smallest of these two elements. If two elements are equal, you can remove any of them (but exactly one).

Your task is to find if it is possible to obtain the array consisting of only one element using several (possibly, zero) such moves or not.

You have to answer $$$t$$$ independent test cases.

## Input Format
The first line of the input contains one integer $$$t$$$ ($$$1 \le t \le 1000$$$) — the number of test cases. Then $$$t$$$ test cases follow.

The first line of the test case contains one integer $$$n$$$ ($$$1 \le n \le 50$$$) — the length of $$$a$$$. The second line of the test case contains $$$n$$$ integers $$$a_1, a_2, \dots, a_n$$$ ($$$1 \le a_i \le 100$$$), where $$$a_i$$$ is the $$$i$$$-th element of $$$a$$$.

## Output Format
For each test case, print the answer: "YES" if it is possible to obtain the array consisting of only one element using several (possibly, zero) moves described in the problem statement, or "NO" otherwise.

## Examples
```input
5
3
1 2 2
4
5 5 5 5
3
1 2 4
4
1 3 4 4
1
100
```
```output
YES
YES
NO
NO
YES
```

## Note
In the first test case of the example, we can perform the following sequence of moves:

- choose $$$i=1$$$ and $$$j=3$$$ and remove $$$a_i$$$ (so $$$a$$$ becomes $$$[2; 2]$$$);
- choose $$$i=1$$$ and $$$j=2$$$ and remove $$$a_j$$$ (so $$$a$$$ becomes $$$[2]$$$).

In the second test case of the example, we can choose any possible $$$i$$$ and $$$j$$$ any move and it doesn't matter which element we remove.

In the third test case of the example, there is no way to get rid of $$$2$$$ and $$$4$$$.

Now solve the problem and return the code.
You are an expert competitive programmer. You will be given a problem statement, test case constraints and example test inputs and outputs. Please reason step by step about the solution (that must respect memory and time limits), then provide a complete implementation in c++17.

Your solution must read input from standard input (cin), write output to standard output (cout).
Do not include any debug prints or additional output.

Put your final solution within a single code block:
```cpp
<your code here>
```

Execution time limit: 2.0 seconds
Memory limit: 256.0 MB

# Problem
There are $$$n$$$ people who want to participate in a boat competition. The weight of the $$$i$$$-th participant is $$$w_i$$$. Only teams consisting of two people can participate in this competition. As an organizer, you think that it's fair to allow only teams with the same total weight.

So, if there are $$$k$$$ teams $$$(a_1, b_1)$$$, $$$(a_2, b_2)$$$, $$$\dots$$$, $$$(a_k, b_k)$$$, where $$$a_i$$$ is the weight of the first participant of the $$$i$$$-th team and $$$b_i$$$ is the weight of the second participant of the $$$i$$$-th team, then the condition $$$a_1 + b_1 = a_2 + b_2 = \dots = a_k + b_k = s$$$, where $$$s$$$ is the total weight of each team, should be satisfied.

Your task is to choose such $$$s$$$ that the number of teams people can create is the maximum possible. Note that each participant can be in no more than one team.

You have to answer $$$t$$$ independent test cases.

## Input Format
The first line of the input contains one integer $$$t$$$ ($$$1 \le t \le 1000$$$) — the number of test cases. Then $$$t$$$ test cases follow.

The first line of the test case contains one integer $$$n$$$ ($$$1 \le n \le 50$$$) — the number of participants. The second line of the test case contains $$$n$$$ integers $$$w_1, w_2, \dots, w_n$$$ ($$$1 \le w_i \le n$$$), where $$$w_i$$$ is the weight of the $$$i$$$-th participant.

## Output Format
For each test case, print one integer $$$k$$$: the maximum number of teams people can compose with the total weight $$$s$$$, if you choose $$$s$$$ optimally.

## Examples
```input
5
5
1 2 3 4 5
8
6 6 6 6 6 6 8 8
8
1 2 2 1 2 1 1 2
3
1 3 3
6
1 1 3 4 2 2
```
```output
2
3
4
1
2
```

## Note
In the first test case of the example, we can reach the optimal answer for $$$s=6$$$. Then the first boat is used by participants $$$1$$$ and $$$5$$$ and the second boat is used by participants $$$2$$$ and $$$4$$$ (indices are the same as weights).

In the second test case of the example, we can reach the optimal answer for $$$s=12$$$. Then first $$$6$$$ participants can form $$$3$$$ pairs.

In the third test case of the example, we can reach the optimal answer for $$$s=3$$$. The answer is $$$4$$$ because we have $$$4$$$ participants with weight $$$1$$$ and $$$4$$$ participants with weight $$$2$$$.

In the fourth test case of the example, we can reach the optimal answer for $$$s=4$$$ or $$$s=6$$$.

In the fifth test case of the example, we can reach the optimal answer for $$$s=3$$$. Note that participant with weight $$$3$$$ can't use the boat because there is no suitable pair for him in the list.

Now solve the problem and return the code.
You are an expert competitive programmer. You will be given a problem statement, test case constraints and example test inputs and outputs. Please reason step by step about the solution (that must respect memory and time limits), then provide a complete implementation in c++17.

Your solution must read input from standard input (cin), write output to standard output (cout).
Do not include any debug prints or additional output.

Put your final solution within a single code block:
```cpp
<your code here>
```

Execution time limit: 2.0 seconds
Memory limit: 256.0 MB

# Problem
You are given a binary string $$$s$$$ consisting of $$$n$$$ zeros and ones.

Your task is to divide the given string into the minimum number of subsequences in such a way that each character of the string belongs to exactly one subsequence and each subsequence looks like "010101 ..." or "101010 ..." (i.e. the subsequence should not contain two adjacent zeros or ones).

Recall that a subsequence is a sequence that can be derived from the given sequence by deleting zero or more elements without changing the order of the remaining elements. For example, subsequences of "1011101" are "0", "1", "11111", "0111", "101", "1001", but not "000", "101010" and "11100".

You have to answer $$$t$$$ independent test cases.

## Input Format
The first line of the input contains one integer $$$t$$$ ($$$1 \le t \le 2 \cdot 10^4$$$) — the number of test cases. Then $$$t$$$ test cases follow.

The first line of the test case contains one integer $$$n$$$ ($$$1 \le n \le 2 \cdot 10^5$$$) — the length of $$$s$$$. The second line of the test case contains $$$n$$$ characters '0' and '1' — the string $$$s$$$.

It is guaranteed that the sum of $$$n$$$ does not exceed $$$2 \cdot 10^5$$$ ($$$\sum n \le 2 \cdot 10^5$$$).

## Output Format
For each test case, print the answer: in the first line print one integer $$$k$$$ ($$$1 \le k \le n$$$) — the minimum number of subsequences you can divide the string $$$s$$$ to. In the second line print $$$n$$$ integers $$$a_1, a_2, \dots, a_n$$$ ($$$1 \le a_i \le k$$$), where $$$a_i$$$ is the number of subsequence the $$$i$$$-th character of $$$s$$$ belongs to.

If there are several answers, you can print any.

## Examples
```input
4
4
0011
6
111111
5
10101
8
01010000
```
```output
2
1 2 2 1 
6
1 2 3 4 5 6 
1
1 1 1 1 1 
4
1 1 1 1 1 2 3 4
```

Now solve the problem and return the code.
You are an expert competitive programmer. You will be given a problem statement, test case constraints and example test inputs and outputs. Please reason step by step about the solution (that must respect memory and time limits), then provide a complete implementation in c++17.

Your solution must read input from standard input (cin), write output to standard output (cout).
Do not include any debug prints or additional output.

Put your final solution within a single code block:
```cpp
<your code here>
```

Execution time limit: 3.0 seconds
Memory limit: 256.0 MB

# Problem
You are given $$$n$$$ segments on a coordinate axis $$$OX$$$. The $$$i$$$-th segment has borders $$$[l_i; r_i]$$$. All points $$$x$$$, for which $$$l_i \le x \le r_i$$$ holds, belong to the $$$i$$$-th segment.

Your task is to choose the maximum by size (the number of segments) subset of the given set of segments such that each pair of segments in this subset either non-intersecting or one of them lies inside the other one.

Two segments $$$[l_i; r_i]$$$ and $$$[l_j; r_j]$$$ are non-intersecting if they have no common points. For example, segments $$$[1; 2]$$$ and $$$[3; 4]$$$, $$$[1; 3]$$$ and $$$[5; 5]$$$ are non-intersecting, while segments $$$[1; 2]$$$ and $$$[2; 3]$$$, $$$[1; 2]$$$ and $$$[2; 2]$$$ are intersecting.

The segment $$$[l_i; r_i]$$$ lies inside the segment $$$[l_j; r_j]$$$ if $$$l_j \le l_i$$$ and $$$r_i \le r_j$$$. For example, segments $$$[2; 2]$$$, $$$[2, 3]$$$, $$$[3; 4]$$$ and $$$[2; 4]$$$ lie inside the segment $$$[2; 4]$$$, while $$$[2; 5]$$$ and $$$[1; 4]$$$ are not.

You have to answer $$$t$$$ independent test cases.

## Input Format
The first line of the input contains one integer $$$t$$$ ($$$1 \le t \le 1000$$$) — the number of test cases. Then $$$t$$$ test cases follow.

The first line of the test case contains one integer $$$n$$$ ($$$1 \le n \le 3000$$$) — the number of segments. The next $$$n$$$ lines describe segments. The $$$i$$$-th segment is given as two integers $$$l_i$$$ and $$$r_i$$$ ($$$1 \le l_i \le r_i \le 2 \cdot 10^5$$$), where $$$l_i$$$ is the left border of the $$$i$$$-th segment and $$$r_i$$$ is the right border of the $$$i$$$-th segment.

Additional constraint on the input: there are no duplicates in the list of segments.

It is guaranteed that the sum of $$$n$$$ does not exceed $$$3000$$$ ($$$\sum n \le 3000$$$).

## Output Format
For each test case, print the answer: the maximum possible size of the subset of the given set of segments such that each pair of segments in this subset either non-intersecting or one of them lies inside the other one.

## Examples
```input
4
4
1 5
2 4
2 3
3 4
5
1 5
2 3
2 5
3 5
2 2
3
1 3
2 4
2 3
7
1 10
2 8
2 5
3 4
4 4
6 8
7 7
```
```output
3
4
2
7
```

Now solve the problem and return the code.
You are an expert competitive programmer. You will be given a problem statement, test case constraints and example test inputs and outputs. Please reason step by step about the solution (that must respect memory and time limits), then provide a complete implementation in c++17.

Your solution must read input from standard input (cin), write output to standard output (cout).
Do not include any debug prints or additional output.

Put your final solution within a single code block:
```cpp
<your code here>
```

Execution time limit: 1.0 seconds
Memory limit: 256.0 MB

# Problem
You are given two integers $$$a$$$ and $$$b$$$.

In one move, you can choose some integer $$$k$$$ from $$$1$$$ to $$$10$$$ and add it to $$$a$$$ or subtract it from $$$a$$$. In other words, you choose an integer $$$k \in [1; 10]$$$ and perform $$$a := a + k$$$ or $$$a := a - k$$$. You may use different values of $$$k$$$ in different moves.

Your task is to find the minimum number of moves required to obtain $$$b$$$ from $$$a$$$.

You have to answer $$$t$$$ independent test cases.

## Input Format
The first line of the input contains one integer $$$t$$$ ($$$1 \le t \le 2 \cdot 10^4$$$) — the number of test cases. Then $$$t$$$ test cases follow.

The only line of the test case contains two integers $$$a$$$ and $$$b$$$ ($$$1 \le a, b \le 10^9$$$).

## Output Format
For each test case, print the answer: the minimum number of moves required to obtain $$$b$$$ from $$$a$$$.

## Examples
```input
6
5 5
13 42
18 4
1337 420
123456789 1000000000
100500 9000
```
```output
0
3
2
92
87654322
9150
```

## Note
In the first test case of the example, you don't need to do anything.

In the second test case of the example, the following sequence of moves can be applied: $$$13 \rightarrow 23 \rightarrow 32 \rightarrow 42$$$ (add $$$10$$$, add $$$9$$$, add $$$10$$$).

In the third test case of the example, the following sequence of moves can be applied: $$$18 \rightarrow 10 \rightarrow 4$$$ (subtract $$$8$$$, subtract $$$6$$$).

Now solve the problem and return the code.