Check this message from the 🗿｜faq channel https://discord.com/channels/793094838509764618/893051131440295966/1017144940305846352 
as far as video resources go, the starknet workshop series and encode videos from the first hackathon earlier this year are great and you can find them on youtube.
I think solidity and cairo compliment each other and you can hear henri's opinion about it here https://youtu.be/UoL4KGP_KVA?t=3794

_This answer was originally posted on [StarkNet Discord](https://www.newton.so/view?tags=discord)_

Newton

Hello everyone. Does anyone happen to know if there's a way to get the block hash in cario? I found out about `get_block_number` and `get_block_timestamp`, but is there something similar for block hash?

_This question was originally posted on [StarkNet Discord](https://www.newton.so/view?tags=discord)_

How to get the block hash in Cairo lang?

I have a question about how to print "Hello World" in Cairo 1. How do I log/print ?

How do I log/print in Cairo 1.0?

 I was able to run those commands without setting up a StarkNet account

When you run warp deploy or warp invoke, which account is paying for the tx fees on the Goerli testnet?

Looking for an implementation of a log function in Cairo


ㅤ
_This question was originally posted on [Triality](https://triality.org/question/495)_

Cairo: How do write a log function in Cairo

Hello! This is day 14 of the 17 days of the Cairo Challenge. And I have no idea how to solve the [playground](https://www.cairo-lang.org/playground/) exercise “Hints”.  Perhaps you can help me?

```
// The following function uses hints to efficiently compute the square root `res`
// of the argument `n`.
// The idea is that the verifier only needs to be convinced that res * res = n,
// it doesn't really care how res was computed.
// In such cases, we don't have to compute res in pure Cairo - we can write a
// piece of Python code inside the Cairo program, which is called a "hint".
// A hint is a piece of code that the prover runs to initialize
// some memory cells. Note that it is completely transparent from the verifier's
// point of view, so the result of the hint *must* be verified using pure Cairo
// instructions (e.g., the "assert n = res * res" instruction below).
//
// 1. Comment out the line "assert n = res * res;" and run the code. Does it still output
//    the expected value? Can you explain why the assert is nonetheless essential?
//    Hint: Recall that from the verifier's point of view, the hint does not exist.
// 2. Uncomment the assert line and change the function to compute the fourth
//    root.

%builtins output

from starkware.cairo.common.serialize import serialize_word

// Computes the square root (over the integers) of `n`.
// Prover assumption: The square root exists.
func sqrt(n) -> (res: felt) {
    alloc_locals;
    local res;

    // Set the value of res using a Python hint.
    %{
        import math

        # Use the ids variable to access the value of a Cairo variable.
        ids.res = int(math.sqrt(ids.n))
    %}

    // From the verifier's point of view, the hint is completely transparent.
    // The following line guarantees that `res` is the square root
    // (either the positive or negative) of `n`.
    assert n = res * res;
    return (res=res);
}

func main{output_ptr: felt*}() {
    let (res) = sqrt(256);
    serialize_word(res);
    return ();
}
```

---

> 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)*

How to use Hints in Cairo Lang?

Hello! I was wondering whether it was possible to check if a certain address has code in Cairo.
In Solidity, we do something like:

```
assembly {
  codeSize := extcodesize(contractAddress)
}
or just:
uint256 codeSize = contractAddress.code;
```
I was wondering if there was a way to check something like this in cairo? I checked the syscalls file but didn't find anything promising there.

Thank you in advance!

How to check if a contract has been deployed at a certain address in cairo?

Python issues with Pathfinder

# Is Kakarot zkEVM a smart contract or a blockchain?

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How to get the block hash in Cairo lang?

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