Is there a way to search a block for events without using `get_transaction_receipt` for each transaction? 

For example, ETH has the `logsBloom` that helps you determine if an event was in the block.
And web3py and many providers have `filter` functions to help you find events.

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

Newton

Is there a way to search a block for events without using `get_transaction_receipt` for each transaction? 

hey! any idea on how much is starknetJS request limit?

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

Do you have any idea on how much is starknetJS request limit?

How to select the network my Pathfinder node runs on?

I'm trying to make a FixedPoint cairo lib, but I'm having some trouble making a pow function. 

It's inspired by this function

```solidity

    function pow(
        uint256 x,
        uint256 y,
        uint256 base
    ) internal pure returns (uint256 z) {
        assembly {
            switch x
            case 0 {
                switch y
                case 0 {
                    // 0 ** 0 = 1
                    z := base
                }
                default {
                    // 0 ** y = 0
                    z := 0
                }
            }
            default {
                switch mod(y, 2)
                case 0 {
                    // If y is even, store base in z for now.
                    z := base
                }
                default {
                    // If y is odd, store x in z for now.
                    z := x
                }

                // Shifting right by 1 is like dividing by 2.
                let half := shr(1, base)

                for {
                    // Shift y right by 1 before looping to halve it.
                    y := shr(1, y)
                } y {
                    // Shift y right by 1 each iteration to halve it.
                    y := shr(1, y)
                } {
                    // Revert immediately if x ** 2 would overflow.
                    // Equivalent to iszero(eq(div(xSquared, x), x)) here.
                    if shr(128, x) {
                        revert(0, 0)
                    }

                    // Store x squared.
                    let xSquared := mul(x, x)

                    // Round to the nearest number.
                    let xSquaredRound := add(xSquared, half)

                    // Revert if xSquared + half overflowed.
                    if lt(xSquaredRound, xSquared) {
                        revert(0, 0)
                    }

                    // Set x to scaled xSquaredRound.
                    x := div(xSquaredRound, base)

                    // If n is even:
                    if mod(y, 2) {
                        // Compute z * x.
                        let zx := mul(z, x)

                        // If z * x overflowed:
                        if iszero(eq(div(zx, x), z)) {
                            // Revert if x is non-zero.
                            if iszero(iszero(x)) {
                                revert(0, 0)
                            }
                        }

                        // Round to the nearest number.
                        let zxRound := add(zx, half)

                        // Revert if zx + half overflowed.
                        if lt(zxRound, zx) {
                            revert(0, 0)
                        }

                        // Return properly scaled zxRound.
                        z := div(zxRound, base)
                    }
                }
            }
        }
    }
```

and I wrote this one in Cairo

```cairo
    func pow{syscall_ptr: felt*, pedersen_ptr: HashBuiltin*, range_check_ptr: felt}(
        x: Uint256,
        n: Uint256,
        baseUnit: Uint256
    ) -> (res: Uint256) {
        alloc_locals;

        let (xIsZero) = uint256_eq(x, Uint256(low=0, high=0));

        if(xIsZero == TRUE) {
            let (nIsZero) = uint256_eq(n, Uint256(low=0, high=0));
            if(nIsZero == TRUE) {
                // 0**0 = 1
                return (res=Uint256(low=1, high=0));
            } 
            // 0**n = 0
            return (res=Uint256(low=0, high=0));            
        }

        let (nHalf, nHalfRem) = uint256_unsigned_div_rem(n, Uint256(low=2, high=0));
        let (nIsEven) = uint256_eq(nHalfRem, Uint256(low=0, high=0));
        let (z) = _assignZIf(nIsEven, baseUnit, x);

        let (baseUnitHalf, baseUnitHalfRem) = uint256_unsigned_div_rem(baseUnit, Uint256(low=2, high=0));

        let (res) = pow_loop(x, nHalf, z, baseUnit, baseUnitHalf);

        return (res=res);
    }

    func pow_loop{syscall_ptr: felt*, pedersen_ptr: HashBuiltin*, range_check_ptr: felt}(
        x: Uint256, 
        n: Uint256, 
        z: Uint256,
        baseUnit: Uint256,
        baseUnitHalf: Uint256
    ) -> (res: Uint256) {
        alloc_locals;
    
        let (n_LteOne) = uint256_le(n, Uint256(low=1, high=0));
        
        if(n_LteOne == TRUE) {
            return (res=z);
        }

        let (xx, xxOverflow) = uint256_mul(x, x);
        assert xxOverflow.low = 0;
        assert xxOverflow.high = 0;

        let (xxRound, xSquaredRoundCarry) = uint256_add(xx, baseUnitHalf);
        let (roundingOverflowed) = uint256_lt(xxRound, xx);
        assert roundingOverflowed = FALSE;

        let (temp_x, temp_x_rem) = uint256_unsigned_div_rem(xxRound, baseUnit);

        let (nHalf, nHalfRem) = uint256_unsigned_div_rem(n, Uint256(low=2, high=0));
        let (nHalfIsEven) = uint256_eq(nHalfRem, Uint256(low=0, high=0));
        if(nHalfIsEven ==  TRUE) {
            let (zx, zxOverflow) = uint256_mul(z, x);
            assert zxOverflow.low = 0;
            assert zxOverflow.high = 0;

            let (shouldBeZ, shouldBeZRem) = uint256_unsigned_div_rem(zx, x);
            let (zxNotOverflowed) = uint256_eq(shouldBeZ, z);
            assert zxNotOverflowed = TRUE;

            let (zxRound, zxRoundCarry) = uint256_add(zx, baseUnitHalf);
            let (zxRoundOverflowed) = uint256_lt(zxRound, zx);
            assert zxRoundOverflowed = FALSE;

            let (temp_z, temp_zRem) = uint256_unsigned_div_rem(zxRound, baseUnit);
            return pow_loop(x=temp_x, n=nHalf, z=temp_z, baseUnit=baseUnit, baseUnitHalf=baseUnitHalf);
        } else {
            return pow_loop(x=temp_x, n=nHalf, z=z, baseUnit=baseUnit, baseUnitHalf=baseUnitHalf);
        }
    }

    func _assignZIf{syscall_ptr: felt*, pedersen_ptr: HashBuiltin*, range_check_ptr: felt}(
        nIsEven: felt,
        baseUnit: Uint256,
        x: Uint256
    ) -> (res: Uint256) {
        if(nIsEven == TRUE) {
            return (res=baseUnit);
        }
        return (res=x);
    }
```

The thing is that I don't get the same results.

Here are some example of my results compared to the solidity function

- pow(1, 3, 10^18): Cairo = 1 / Solidity = 0

- pow(10^18, 5, 10^18): Cairo = 4000000000000000000 (4x10^18) / Solidity = 32000000000000000000 (32x10^18)

- pow(10^19, 5, 10^18): Cairo = 100000000000000000000 (10^20) / Solidity = 100000000000000000000000 (10^23)

I can't see what I'm doing wrong in my code

Fixed Point pow operation error

Hello! This is day 4 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 “Variables”. Can you launch this code with the instructions and write down how many steps the program has in the output?

[BONUS]: try to make it faster

```
// The following code outputs the 9th power of 2.
// 1. Click on "Debug" to run the code, and then click on
//    the arrows in the memory panel to trace the program
//    step by step.
//
// Observe that the computation of `z` take 8 steps and
// creates 8 temporary variables. This is because `let`
// simply replaces each instance of `y` with `x * x * x`
// and each instance of `z` with `y * y * y`, which is
// expanded to nine multiplications.
//
// 2. Change the two `let`s to `tempvar`s and run the program.
//
// "tempvar" stands for "temporary variable", which means that
// a variable will be allocated for the intermediate values
// (`x * x * x` and `y * y * y`). This reduces the same
// computation to use only 4 steps and 2 new variables.
//
// 3. Replace all three instance of the keyword `tempvar`
//    with `local`, uncomment the line containing `alloc_locals`
//    and run the code again.
//
// The behavior of the code doesn't change. This is because
// the keyword `local` allocates a new variables for the
// intermediate values as well. The main difference between
// `local` and `tempvar` is explained in the next challenge.

// Use the output builtin.
%builtins output

// Import the serialize_word() function.
from starkware.cairo.common.serialize import serialize_word

// Outputs the value 2^9.
func main{output_ptr: felt*}() {
    // alloc_locals;
    tempvar x = 2;
    let y = x * x * x;
    let z = y * y * y;
    // Because of the `let`s, the following line is equivalent to
    // serialize_word(x * x * x * x * x * x * x * x * x).
    serialize_word(z);
    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)*

What is the difference between tempvar/let in Cairo Lang? How to use allow_locals and local?

does anyone know how to import an account to ArgentX by private key?

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

Does anyone know how to import an account to ArgentX by private key?

Hi guys. What can I do if I've sent transactions from StarkNet to Ethereum L2 -> L1 on mainnet, withdraw was initiated and funds left from Starknet wallet but I don't see any pop up to process L1 deposit? It was 22h ago.

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

What can I do if I've sent transactions from StarkNet to Ethereum L2 -> L1 on mainnet and transaction got stacked?

I have an array in Cairo


`let (myArr : felt*) = alloc()`


How do I set the 1st and 2nd term and get the first and second term?


ㅤ
_This question was originally posted on [Triality](https://triality.org/question/588)_

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