**Step 2:**
If you cannot install  `ecdsa `or `fastecdsa`. Maybe you need to install python3.9-dev

```
sudo apt install python3.9-venv
```
**Step 4:**
```
from starkware.cairo.common.serialize import serialize_word
from starkware.cairo.common.alloc import alloc

struct KeyValue {
    key: felt,
    value: felt,
}

func main() {
    //Create an array with 5 KeyValue elments [(3, 5), (1, 10), (3, 1), (3, 8), (1, 20)]
    alloc_locals;
    let (array: KeyValue*) = alloc();
    assert array[0] = KeyValue(key=3, value=5); 
    assert array[1] = KeyValue(key=1, value=10); 
    assert array[2] = KeyValue(key=3, value=1); 
    assert array[3] = KeyValue(key=3, value=8); 
    assert array[4] = KeyValue(key=1, value=20); 
    
    //print 5th element
    %{
        
        el = ids.array.address_ + ids.KeyValue.SIZE * 4
        print([memory[el + 0]])
        print([memory[el + 1]])
    %}
    return ();
}
```
**Last step:**

Output should be like that

```
[1]
[20]
Number of steps: 25 (originally, 25)
Used memory cells: 67
Register values after execution:
pc = 58
ap = 58
fp = 58
```



Hello! This is day 17 of the 17 days of the Cairo Challenge. In this challenge I want to ask you [install](https://www.cairo-lang.org/docs/quickstart.html) Cairo and try to launch your first program. What have you implemented as your first Cairo language program?

**Step 1**
```solidity
// 1. Make sure that you installed dev packages on your device
sudo apt install -y libgmp3-dev // Linux
brew install gmp // Mac OS
```
**Step 2**
```solidity
// 2. Install Cairo using Python virtual environment
python3.9 -m venv ~/cairo_venv
source ~/cairo_venv/bin/activate
pip3 install ecdsa fastecdsa sympy;
pip3 install cairo-lang;
```
**Step 3**
```bash
// 3. Make sure you have python 3.9. Because Cairo was tested with python3.9. To make it work with python3.6, you will have to install contextvars:
pip3 install contextvars
```
**Step 4**
```python
// 4. Write your program
// Create a file, named hello.cairo, with the following lines:
 
func main() {
		// edit me: you can add here any output, best program wins the challenge
    ret;
}

```solidity
//5. Compile your program
cairo-compile hello.cairo --output hello_compiled.json
```
**Last step**
```solidity

//6. Run:
cairo-run \
  --program=hello_compiled.json --print_output \
  --print_info --relocate_prints

//7. Debug:
//You can open the Cairo tracer by providing the --tracer flag to cairo-run. Then open it at http://localhost:8100/.
```
If you have questions, create them on Newton and we will help!

---
> Answers to this question are a part of the ✨ 17 days of Cairo Lang with Playground & Newton. ✨
> 

*Vote for your favorite answer - the best answer will win a $10 award. A new day – a new reward! During the next 17 days, our goal is to attract more developers to the Cairo language and to systematize the knowledge of Cairo lang. [Read rules](https://www.notion.so/17-days-of-Cairo-Lang-with-Newton-550dfcda6a2d449ca468be293c776578)*

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