ques-2.cairo

%lang starknet
from starkware.cairo.common.math import assert_nn
from starkware.cairo.common.cairo_builtins import HashBuiltin
from starkware.cairo.common.alloc import alloc
from starkware.cairo.common.find_element import find_element
from starkware.cairo.common.uint256 import (
    Uint256,
    uint256_eq,
    uint256_le,
    uint256_lt,
    uint256_signed_div_rem,
)
from starkware.cairo.common.math import assert_nn_le, split_felt, unsigned_div_rem
from starkware.cairo.common.bool import FALSE, TRUE
from starkware.cairo.common.default_dict import default_dict_new
from starkware.cairo.common.dict import dict_read, dict_write
from starkware.cairo.common.dict_access import DictAccess
from starkware.cairo.common.math_cmp import is_le

func reverse_arr{syscall_ptr : felt*, pedersen_ptr : HashBuiltin*, range_check_ptr}(
    array_len : felt, array : felt*
) -> (rev_array_len : felt, rev_array : felt*):
    if array_len == 0:
        let (rev_array) = alloc()
        return (0, rev_array)
    end

    let (rev_array_len, rev_array) = reverse_arr(array_len - 1, array + 1)
    assert rev_array[rev_array_len] = array[0]
    return (rev_array_len + 1, rev_array)
end