Solidity Solidity Data Types and Storage

Question 1

Which of the following is a value type in Solidity?

Accepted Answer

uint256

Answer

bytes (dynamic)

Answer

string

Answer

mapping

Question 2

What is the default value of an uninitialized bool state variable in Solidity?

Accepted Answer

false

Answer

null

Answer

true

Answer

undefined

Question 3

What is the maximum value that can be stored in a uint8 in Solidity?

Accepted Answer

255

Answer

127

Answer

256

Answer

65535

Question 4

Which Solidity type correctly declares a fixed-size byte array of exactly 32 bytes?

Accepted Answer

bytes32

Answer

byte[32]

Answer

bytes(32)

Answer

fixed32

Question 5

What is the key difference between int256 and uint256 in Solidity?

Accepted Answer

int256 can store negative values while uint256 cannot

Answer

int256 uses less gas than uint256

Answer

uint256 can only store even numbers

Answer

They are identical types with different names

Question 6

What is the byte size of the address type in Solidity?

Accepted Answer

20 bytes

Answer

16 bytes

Answer

32 bytes

Answer

64 bytes

Question 7

Which Solidity integer type is recommended for most use cases to avoid implicit conversion issues?

Accepted Answer

uint256

Answer

int8

Answer

uint32

Answer

int128