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Fast CSV parser in C++

An efficient method for parsing or for that matter processing of files is to read as much of the file into memory before you start parsing.

File I/O has been, since the dawn of computers, one of the slower parts of a computer system. For example, parsing your data may take 1 microsecond. Reading the data from a hard drive may take 1 millisecond == 1000 microseconds.

I've made programs faster by allocating a large array for the data then reading the data into the array. Next I process the data in the array and repeat until the entire file is processed.

Another technique is called memory mapping, where the OS handles reading the file into memory as needed.

Please edit your post to show the code where the bottleneck is.

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