cpp / beginner
Snippet
Type Casting: Converting Between Data Types
Type casting converts a value from one data type to another. C++ provides static_cast for compile-time type conversions between related types like numbers and characters. When casting a double to an int, the decimal portion is truncated (not rounded). When casting an int to a double, the value remains the same but gains a decimal point. Casting a char to an int reveals its ASCII numeric value, where 'A' equals 65.
snippet.cpp
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#include <iostream>int main() {int wholeNumber = 42;double pi = 3.14159;double fromInt = static_cast<double>(wholeNumber);int fromDouble = static_cast<int>(pi);std::cout << "Integer as double: " << fromInt << std::endl;std::cout << "Double as integer: " << fromDouble << std::endl;char letter = 'A';int asInt = static_cast<int>(letter);std::cout << "Char 'A' as integer: " << asInt << std::endl;return 0;}
Breakdown
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int wholeNumber = 42;
Integer variable with value 42
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double pi = 3.14159;
Double variable with decimal value
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double fromInt = static_cast<double>(wholeNumber);
Converts int to double, result is 42.0
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int fromDouble = static_cast<int>(pi);
Converts double to int, truncates to 3
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std::cout << "Integer as double: " << fromInt << std::endl;
Prints converted double value
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std::cout << "Double as integer: " << fromDouble << std::endl;
Prints truncated integer value
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char letter = 'A';
Character variable holding letter A
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int asInt = static_cast<int>(letter);
Converts char to its ASCII numeric value
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std::cout << "Char 'A' as integer: " << asInt << std::endl;
Prints ASCII value 65