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# asm1

### Challenge Description

We are given the assembly code of a function `asm1` and asked:

> What does `asm1(0x27)` return? Submit the answer in hexadecimal format (starting with `0x`).

***

### Step 1: Understanding the Assembly

Relevant assembly:

```
<+7>:  cmp DWORD PTR [ebp+0x8], 0x4ee
<+14>: jg  <asm1+38>

<+16>: cmp DWORD PTR [ebp+0x8], 0x27
<+20>: jne <asm1+30>

<+22>: mov eax, [ebp+0x8]
<+25>: add eax, 0x12
<+28>: jmp <asm1+61>

<+30>: mov eax, [ebp+0x8]
<+33>: sub eax, 0x12
```

<https://www.codeconvert.ai/assembly-to-c-converter?id=6eccffaf-6eac-42e0-95e8-fa924cedf0a2>

<img src="https://github.com/user-attachments/assets/64f61f3d-655e-4f20-b36a-6387b1e8338a" alt="image" height="355" width="1034">

This translates to the following C-like logic:

```c
int asm1(int x) {
    if (x > 0x4ee) {
        if (x == 0x7b8) {
            return x - 0x12;
        } else {
            return x + 0x12;
        }
    } else {
        if (x == 0x27) {
            return x + 0x12;
        } else {
            return x - 0x12;
        }
    }
}
```

***

### Step 2: Evaluate the Input

We are given:

```
x = 0x27
```

#### Check first condition:

```
x > 0x4ee
0x27 > 0x4ee → false
```

So execution moves to the `else` block.

***

### Step 3: Evaluate Inner Condition

```
if (x == 0x27)
```

This is true, since:

```
x = 0x27
```

So we execute:

```
return x + 0x12
```

***

### Step 4: Compute the Result

```
0x27 + 0x12
```

Convert to decimal:

```
0x27 = 39
0x12 = 18
```

Add:

```
39 + 18 = 57
```

Convert back to hex:

```
57 = 0x39
```

***

### Final Answer

```
0x39
```

***

### Key Takeaways

* Always follow the control flow using `cmp` and conditional jumps (`jg`, `jne`).
* Map assembly to simple C logic for clarity.
* Evaluate conditions step-by-step with the given input.
* Keep everything consistent in hexadecimal when required.


---

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