Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Blockchain-based Smart Contracts: A Systematic Mapping Study   An appealing feature of blockchain technology is smart contracts. A smart
contract is executable code that runs on top of the blockchain to facilitate,
execute and enforce an agreement between untrusted parties without the
involvement of a trusted third party. In this paper, we conduct a systematic
mapping study to collect all research that is relevant to smart contracts from
a technical perspective. The aim of doing so is to identify current research
topics and open challenges for future studies in smart contract research. We
extract 24 papers from different scientific databases. The results show that
about two thirds of the papers focus on identifying and tackling smart contract
issues. Four key issues are identified, namely, codifying, security, privacy
and performance issues. The rest of the papers focuses on smart contract
applications or other smart contract related topics. Research gaps that need to
be addressed in future studies are provided.

2
The categories of this paper are: math
26
The categories of this paper are: bayes-an
8
The categories of this paper are: hep-ex
23
The categories of this paper are: solv-int
3
The categories of this paper are: physics
35
The categories of this paper are: mtrl-th
12
The categories of this paper are: nucl-th
29
The categories of this paper are: funct-an
27
The categories of this paper are: comp-gas
17
The categories of this paper are: q-fin
30
The categories of this paper are: q-alg
0
The categories of this paper are: hep-ph
6
The categories of this paper are: astro-ph
10
The categories of this paper are: q-bio
34
The categories of this paper are: chem-ph
16
The categories of this paper are: stat