[INSTRUCTIONS]

You are a program-analysis assistant. Your task is to statically analyze the control dependence of a given code snippet. 

## 1. Control Dependence Definition
  Control dependence captures the influence of control-flow decisions on the execution of statements.

  A statement `S2` is control-dependent on `S1` if there is a **transitive** (indirect) chain of **direct** control dependencies from `S1` to `S2`. This is equivalent to saying that `S1` has control dependence over `S2`, meaning `S1`’s condition influences whether `S2` executes.


  **Direct Control Dependence**:
  A statement `S2` is **directly** control-dependent on a statement `S1` if:
  
  1.	`S1` is a conditional control statement (e.g., an `if`, `while`, `for`, `switch`, etc.).
  
  2.	`S1` directly determines whether `S2` executes. That is, `S1` has multiple successor branches, 

  - there exists **at least one branch** in which `S2` **always executes**, and
  - there exists **at least one other branch** in which `S2` does **not necessarily execute**.

    “Not necessarily execute” means that `S2` might execute or might not, but it is **not guaranteed** to execute in that branch.

  `S2` is **control-dependent** on `S1` if there exists a **transitive chain** of control dependencies from `S1` to `S2`, where each intermediate step in the chain represents a **direct** control dependence between two statements.



## 2. Output Format
When asked, “Does line `S1` have control dependence over line `S2`? If so, provide a trace.” You should respond in JSON format as follows:

- If there is a control dependence:

```json
{
  "ControlDependence": true,
  "Trace": [S1, ..., S2]
}
```

- If there is no control dependence:
```json
{
  "ControlDependence": false
}
```

A **trace** represents a **transitive control flow**, where each adjacent pair in the list reflects a **direct** control dependence. The trace must starts with `S1` and ends with `S2`.


    

## 3. Interprocedural Control Dependence
  All dependence analysis is performed within **a single function**. We do not track dependencies across function boundaries. The analysis only applies to variables and control structures inside the **specified function**.


## 4. Example Code Snippet

### Example 1

```python
1  if x > 0:
2      y = 10       # this line is directly control-dependent on line 1 (x>0)
3      if y > 5:
4          z = 20   # this line is directly control-dependent on line 3 (y>5)
5          w = 30   # this line is directly control-dependent on line 3 (y>5)
6  v = 40           # this line is NOT control-dependent on any line
```


**Analysis**:
- Line 2 is directly control-dependent on line 1 (`x>0`)
- Lines 4 and 5 are directly control-dependent on line 3 (`y>5`).
- Lines 4 and 5 are **indirectly** control-dependent on line 1 (`x>0`) becasue even if line 1 (`x>0`) is `true`, lines 4 and 5 may not execute if line 3’s condition (`y>5`) is `false`. However, since control dependence is transitive, lines 4 and 5 are **indirectly** control-dependent on line 1. 
- Line 6 is not control-dependent on any lines because Line 6 always executes, regardless of whether line 1 (`x>0`) or line 3 (`y>5`) is true or false.



#### Example Question 1.1: 
Does line `1` have control dependence over line `5`? If so, provide a trace.

**Output**: 
```json
{
  "ControlDependence": true,
  "Trace": [1, 3, 5]
}
```

#### Example Question 1.2:
Does line `3` have control dependence over line `6`? If so, provide a trace.

**Output**: 
```json
{
  "ControlDependence": false
}
```


### Example 2

```python
1  count = 0
2  if count < 5:
3      count += 1
4  print("Step 1 done")
5  while count < 10:
6      if count == 7:
7          break
8      if count % 2 == 0:
9          continue
10     count += 2
11     if count > 9:
12         count = 9
13     print("Iteration done")
14 print("End of program")
```

#### Example Question 2.1: 
Does line `5` have control dependence over line `13`? If so, provide a trace.

**Analysis**:
  - Line 13 is directly control-dependent on line 8 because if line 8 evaluates to `true`, continue skips line 13 for that iteration.
  - Line 8 is directly control-dependent on line 6 because if line 6 evaluates to `true`, the break statement terminates the loop, preventing line 8 from executing.
  - Line 6 is directly control-dependent on line 5 because the loop condition at line 5 determines whether line 6 executes. If line 5 evaluates to `false`, execution skips the loop entirely.


Since control dependence is transitive, line 5 indirectly controls line 13 through lines 6 and 8. The trace is `5->6->8->13`.

**Output**:
```json
{
  "ControlDependence": true,
  "Trace": [5, 6, 8, 13]
}
```

#### Example Question 2.2: 
Does line `8` have control dependence over line `10`? If so, provide a trace.


**Analysis**: Similar to the explanation above, line 8 is an `if` condition inside the `while` loop with a `continue`, so it can make the execution skip the rest of the loop entirely, including line 10. Therefore, line 10 directly control-dependent on 8.



**Output**:
```json
{
  "ControlDependence": true,
  "Trace": [8, 10]
}
```

#### Example Question 2.3: 
Does line `5` have control dependence over line `14`? If so, provide a trace.

**Analysis**: Line 5 doesn't affect whether line 14 is reached. Line 14 is outside the while loop (lines 5 -- 13) and will be executed regardless of the condition. 

**Output**:
```json
{
  "ControlDependence": false
}
```


#### Example Question 2.4: 
Does line `2` have control dependence over line `12`? If so, provide a trace.

**Analysis**: Line 2 doesn't affect whether line 12 is reached. The condition in line 2 only controls whether line 3 is executed. Line 12 is in while loop (line 5 -- 13) and will or will not be executed regardless of the condition in line 2. 

**Output**:
```json
{
  "ControlDependence": false
}
```

---

[YOUR TURN]

Below is **your target snippet**. 

```C
1   #define _CRT_SECURE_NO_WARNINGS
2   #include<stdio.h>
3   #include<string.h>
4   #include<stdbool.h>
5   #include<stdlib.h>
6   #include<math.h>
7   #include<malloc.h>
8   void CodeJam(int n)
9   {
10  	int i, j, k;
11  	k = 0;
12  	char tmp[1000][51];
13  	char word[1000][51];
14  	char rw[1000][51];
15  	int match[1000] = { 0, };
16  	int max[1000] = { 0, };
17  	for (i = 0; i != n; i++)
18  	{
19  		scanf("%s", word[i]);
20  	}
21  	for (i = 0; i != 1000; i++)
22  	{
23  		for (j = 0; j != 50; j++)
24  		{
25  			rw[i][j] = word[i][j];
26  		}
27  	}
28  	for (i = 0; i != n; i++)
29  	{
30  		for (j = 0; j != strlen(word[i]); j++)
31  		{
32  			rw[i][j] = word[i][strlen(word[i]) - j - 1];
33  		}
34  	}
35  	for (i = 0; i != n - 1; i++)
36  	{
37  		for (j = 0; j != n - 1 - i; j++)
38  		{
39  			if (strcmp(word[j], word[j + 1]) > 0)
40  			{
41  				strcpy(tmp[j], word[j]);
42  				strcpy(word[j], word[j + 1]);
43  				strcpy(word[j + 1], tmp[j]);
44  			}
45  		}
46  	}
47  	for (i = 0; i != n - 1; i++)
48  	{
49  		for (j = 0; j != strlen(rw[i]) > strlen(rw[i + 1]) ? strlen(rw[i + 1]) : strlen(rw[i]); j++)
50  		{
51  			if (rw[i][j] == rw[i + 1][j])
52  			{
53  				match[i]++;
54  			}
55  			else
56  			{
57  				break;
58  			}
59  		}
60  	}
61  	max[0] = match[0];
62  	max[1] = match[1];
63  	for (i = 2; i != 1000; i++)
64  	{
65  		max[i] = max[i - 2] + match[i];
66  	}
67  	printf("%d\n", max[999] > max[998] ? max[999] : max[998]);
68  }
69  int main()
70  {
71  	int i;
72  	int t;
73  	scanf("%d", &t);
74  	for (i = 1; i <= t; ++i)
75  	{
76  		printf("Case #%d: ", i);
77  		int N;
78  		scanf("%d", &N);
79  		CodeJam(N);
80  	}
81  	return 0;
82  }
```


**Question**: Does line `21` have control dependence over line `53` in function `CodeJam`? If so, provide a trace.

**Output**:


Ground truth answer: no