Hi,
`invoke` like in `invokeFunction` on the Provider ? 
1- There is nothing wrong about using strings. You should use string as you can see from the type that is used in the `invokeFunction` here https://github.com/0xs34n/starknet.js/blob/b4785793ea912dc8562de4c69b0dcbda4358e144/src/types/lib.ts#L20
2- The correct way to proceed (assuming you want to write to the blockchain) would be (1) create an account and (2) `execute` a contract function from that account. But before that, did you connect to your wallet? How did you do that? The way it works is the transaction needs to be signed by the user and the easiest way is definitely to ask your wallet to sign it for you.
3- You also need to check the version of starknet-js. What version are you using?
4- If you are stuck, there are several things you could do: (1) find an example and make sure it works; (2) explain where you are stuck (3) provide the code extract and the exact error message you get in details

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

Newton

Hi everyone,

When i try to invoke my functions with arguments from my frontend app using starknetjs, i get error invalid character, which i presume is an issue from my function accepting felt, but i'm passing texts. Is there any way to convert to felts from the browser or does starknetjs do this by default?

Anyone knows how i can solve the error?

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

How to fix invalid character error while invoking starknetjs frontend app in Cairo?

What’s the difference between Account Abstraction (AA) and Externally Owned Accounts (EOA)?

---

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What’s the difference between Account Abstraction (AA) and Externally Owned Accounts (EOA)?


I'm trying to solve [this bonus question](https://www.cairo-lang.org/docs/how_cairo_works/program_counter.html#program-counter-and-jumps) from the "How Cairo Works" tutorial. I ran the following function, opened the Cairo tracer and saw that the memory is full with powers of 2. Why is that?



```
func main():
    [fp + 1] = 2; ap++
    [fp] = 5201798304953761792; ap++
    jmp rel -1
end

```

[![enter image description here](https://i.stack.imgur.com/julcJ.jpg)](https://i.stack.imgur.com/julcJ.jpg)



ㅤ
_This question was originally posted on [Stack Overflow](https://stackoverflow.com/questions/71500794/why-does-this-cairo-program-put-powers-of-2-in-the-memory)_

Why does this Cairo program put powers of 2 in the memory?

Since memory cannot be freed, what's the drawback of only using local variables (to avoid revoked refs)? What's the typical use case for tempvars?


ㅤ
_This question was originally posted on [Triality](https://triality.org/question/512)_

Cairo: When do you use tempvar and when do you use local

Why am I getting the error message `“ArgumentsLengthError: The number of the given arguments (0) do not match what is defined in the ABI (1)”`


ApeWorX: Why am I getting the error message "ArgumentsLengthError"?

Hello! This is day 7 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 “Recursion”.  Perhaps you can help me?

```
// The following code prints the sum of the numbers from 1 to 10.
// Modify the function `compute_sum` to print all the intermediate sums:
// 1, 1 + 2, 1 + 2 + 3, ..., 1 + 2 + ... + 10.
// Note: you'll have to add the implicit argument output_ptr to the
// declaration of compute_sum (in order to use the serialize_word function):
//   func compute_sum{output_ptr: felt*}(n: felt) -> (sum: felt)

// Use the output builtin.
%builtins output

from starkware.cairo.common.serialize import serialize_word

func compute_sum(n: felt) -> (sum: felt) {
    if (n == 0) {
        // When 0 is reached, return 0.
        return (sum=0);
    }

    // Otherwise, call `compute_sum` recursively to compute 1 + 2 + ... + (n-1).
    let (sum) = compute_sum(n=n - 1);
    // Add the new value `n` to the sum.
    let new_sum = sum + n;
    return (sum=new_sum);
}

func main{output_ptr: felt*}() {
    let (res) = compute_sum(n=10);

    // Output the result.
    serialize_word(res);
    return ();
}
```

---

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> 
*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 make recursive function in Cairo Lang?

# Hello world!

I try to implement the function `abs_value` of the package `starkware.cairo.common.math` but i have this error

```
AssertionError: Expected main to contain the following arguments (in this order): ['range_check_ptr_ptr']. Found: ['range_check_ptr'].
```

I dont understand the error. 

Can someone explain the error to me, why it happens ? 

> I am doing the challenge #17daysOfCairo of the day 3


Full code

```
%builtins range_check_ptr
from starkware.cairo.common.math import abs_value

func main{range_check_ptr}() {
    let x = abs_value(-1);
    return ();
}
```


AssertionError with range_check_ptr_ptr

hi guys! is it possible to import local python files into hints?

Like so:
```python
# Cairo here

%{
	import my_python_file.py
	# Python here
%}
```

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