Casting and Range of Variables - AP Computer Science A
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What is the range of a char in Java?
What is the range of a char in Java?
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$0$ to $65535$ (unsigned). 16-bit Unicode characters from 0 to 65535.
$0$ to $65535$ (unsigned). 16-bit Unicode characters from 0 to 65535.
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What is a potential issue when casting long to int?
What is a potential issue when casting long to int?
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Loss of data if the value exceeds int range. Values outside int range cause overflow.
Loss of data if the value exceeds int range. Values outside int range cause overflow.
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What is the result of casting int to boolean?
What is the result of casting int to boolean?
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Not allowed; compile-time error. boolean and numeric types are incompatible.
Not allowed; compile-time error. boolean and numeric types are incompatible.
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Identify the cast needed to convert char to byte.
Identify the cast needed to convert char to byte.
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Explicit cast: (byte) value. Narrowing from 16-bit to 8-bit integer.
Explicit cast: (byte) value. Narrowing from 16-bit to 8-bit integer.
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Find the cast needed to convert long to int.
Find the cast needed to convert long to int.
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Explicit cast: (int) value. Narrowing conversion from 64-bit to 32-bit.
Explicit cast: (int) value. Narrowing conversion from 64-bit to 32-bit.
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Which data type is used for precise decimal values?
Which data type is used for precise decimal values?
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double. double provides highest precision for decimals.
double. double provides highest precision for decimals.
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What is underflow in the context of variable casting?
What is underflow in the context of variable casting?
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Underflow is exceeding the minimum range of a data type. Value wraps around when below minimum.
Underflow is exceeding the minimum range of a data type. Value wraps around when below minimum.
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How would you cast int to byte?
How would you cast int to byte?
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Explicit cast: (byte) value. Narrowing conversion from 32-bit to 8-bit.
Explicit cast: (byte) value. Narrowing conversion from 32-bit to 8-bit.
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What is a narrowing conversion?
What is a narrowing conversion?
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Converting a larger data type to a smaller one. Potential data loss when reducing precision.
Converting a larger data type to a smaller one. Potential data loss when reducing precision.
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What is a widening conversion?
What is a widening conversion?
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Converting a smaller data type to a larger one. Preserves data when increasing capacity.
Converting a smaller data type to a larger one. Preserves data when increasing capacity.
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What keyword is used to explicitly cast types?
What keyword is used to explicitly cast types?
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Cast operator, e.g., (int) or (float). Parentheses with target type name.
Cast operator, e.g., (int) or (float). Parentheses with target type name.
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What happens when casting float to int?
What happens when casting float to int?
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The fractional part is truncated. Decimal portion removed, not rounded.
The fractional part is truncated. Decimal portion removed, not rounded.
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What is the result of casting char to int?
What is the result of casting char to int?
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The Unicode value of the character. char represents Unicode code points.
The Unicode value of the character. char represents Unicode code points.
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Can you implicitly cast int to float?
Can you implicitly cast int to float?
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Yes, int can be implicitly cast to float. int fits within float's range safely.
Yes, int can be implicitly cast to float. int fits within float's range safely.
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What is type promotion in expressions?
What is type promotion in expressions?
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Automatic conversion of types to prevent data loss. Smaller types promoted to avoid overflow.
Automatic conversion of types to prevent data loss. Smaller types promoted to avoid overflow.
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What is the effect of casting int to char?
What is the effect of casting int to char?
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Character representation of the int value. Unicode value converted to character symbol.
Character representation of the int value. Unicode value converted to character symbol.
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What are primitive data types in Java?
What are primitive data types in Java?
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byte, short, int, long, float, double, char, boolean. Eight basic data types built into Java.
byte, short, int, long, float, double, char, boolean. Eight basic data types built into Java.
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What is the purpose of casting in programming?
What is the purpose of casting in programming?
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To convert one data type to another. Ensures compatibility between different data types.
To convert one data type to another. Ensures compatibility between different data types.
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Which data type has the largest range: int, short, or byte?
Which data type has the largest range: int, short, or byte?
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int. int has 32 bits vs 16 for short, 8 for byte.
int. int has 32 bits vs 16 for short, 8 for byte.
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What is the range of a double in Java?
What is the range of a double in Java?
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Approximately $1.7 \times 10^{-308}$ to $1.7 \times 10^{308}$. 64-bit IEEE 754 floating-point precision.
Approximately $1.7 \times 10^{-308}$ to $1.7 \times 10^{308}$. 64-bit IEEE 754 floating-point precision.
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What is the range of a float in Java?
What is the range of a float in Java?
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Approximately $3.4 \times 10^{-38}$ to $3.4 \times 10^{38}$. 32-bit IEEE 754 floating-point precision.
Approximately $3.4 \times 10^{-38}$ to $3.4 \times 10^{38}$. 32-bit IEEE 754 floating-point precision.
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What is the range of a long in Java?
What is the range of a long in Java?
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$-2^{63}$ to $2^{63}-1$. Standard 64-bit signed integer range.
$-2^{63}$ to $2^{63}-1$. Standard 64-bit signed integer range.
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What is the range of a byte in Java?
What is the range of a byte in Java?
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$-2^{7}$ to $2^{7}-1$. Standard 8-bit signed integer range.
$-2^{7}$ to $2^{7}-1$. Standard 8-bit signed integer range.
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What is the range of a short in Java?
What is the range of a short in Java?
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$-2^{15}$ to $2^{15}-1$. Standard 16-bit signed integer range.
$-2^{15}$ to $2^{15}-1$. Standard 16-bit signed integer range.
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What is the range of an int in Java?
What is the range of an int in Java?
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$-2^{31}$ to $2^{31}-1$. Standard 32-bit signed integer range.
$-2^{31}$ to $2^{31}-1$. Standard 32-bit signed integer range.
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How do you cast an int to a double?
How do you cast an int to a double?
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Implicit cast: No cast needed. Widening conversion happens automatically.
Implicit cast: No cast needed. Widening conversion happens automatically.
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What happens when you cast a larger type to a smaller type?
What happens when you cast a larger type to a smaller type?
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Possible data loss or precision loss. Narrowing conversions truncate or overflow values.
Possible data loss or precision loss. Narrowing conversions truncate or overflow values.
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Identify the cast needed to convert double to int.
Identify the cast needed to convert double to int.
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Explicit cast: (int) value. Narrowing conversion requires explicit cast operator.
Explicit cast: (int) value. Narrowing conversion requires explicit cast operator.
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What is implicit casting?
What is implicit casting?
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Implicit casting is automatic type conversion by the Java compiler. Happens when widening conversions are safe.
Implicit casting is automatic type conversion by the Java compiler. Happens when widening conversions are safe.
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What is explicit casting?
What is explicit casting?
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Explicit casting is manually converting a data type using a cast operator. Required for narrowing conversions to prevent data loss.
Explicit casting is manually converting a data type using a cast operator. Required for narrowing conversions to prevent data loss.
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