"std::endl" vs "\n" which is faster
Today, we will discuss basic techniques in C++. It is the new line character. In C++ we have two ways to print out a new lines.
- printf("\n");
- using std::cout << std::endl;
The question is which one is faster?
Answer:
'\n'
is significantly faster than std::endl
in C++.
Here's why:
\n
is simply a newline character. It inserts a new line into the output stream without any additional operations.
std::endl
does two things:
- Inserts a newline character.
- Flushes the output buffer.
Flushing the output buffer forces the contents of the buffer to be written to the actual output device (like the console or a file). This operation can be quite expensive, especially if done frequently. In most cases, you don't need to explicitly flush the output buffer. The buffer is automatically flushed when:
- The buffer is full.
- The program terminates.
- An input operation is performed (e.g., cin).
Therefore, using \n
is generally the preferred choice for performance reasons. Only use std::endl
if you specifically need to force a flush of the output buffer.
Example:
1#include
2int main() {
3 for (int i = 0; i < 1000000; ++i) {
4 std::cout << "Hello, world!\n"; // Faster
5 // std::cout << "Hello, world!" << std::endl; // Slower
6 }
7 return 0;
8}
Use code with caution.
In this example, using \n
will result in significantly faster execution compared to using std::endl
.
Remember: While performance is important, readability and maintainability are also crucial factors. If you need to explicitly flush the output buffer for specific reasons, using std::endl
is acceptable. However, in most cases, \n is the better choice.
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