What is << symbol in C++?
In C++, the << symbol is an overloaded operator that can be used in two main contexts:
1. Output Stream Operator
When used with the std::cout object, the << operator is called the insertion operator. It is used to output data to the console (standard output).
Example:
int x = 10; std::cout << "The value of x is: " << x << std::endl;
- In this case,
<<takes the value ofxand "inserts" it into the output stream, displaying it in the console. - The output for the above code would be:
The value of x is: 10
2. Bitwise Left Shift Operator
The << operator is also used as the bitwise left shift operator. It shifts the bits of an integer to the left by a specified number of positions, effectively multiplying the number by powers of two.
Example:
int a = 5; // Binary: 0000 0101 int result = a << 1; // Left shift by 1 bit
- After the left shift,
abecomes0000 1010, which is10in decimal. - The left shift operator can be used for efficient multiplication by powers of two.
Summary:
std::cout <<: Used to print values to the console.<<as bitwise operator: Shifts bits to the left, typically used in low-level programming.
Sources:
TAGS
Coding Interview
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Arslan Ahmad
ex-FAANG engineering manager and author or Grokking series.
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