What's least expensive? (memory)

[codeslicer]

What would be least expensive in this situation?

QStringList lineStringList = file->readLine().split("\t");

QStringList lineStringList = file->readLine().split("\t");

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or

QString lineString = file->readLine();
QStringList lineStringList = lineString.split("\t");

QString lineString = file->readLine();
QStringList lineStringList = lineString.split("\t");

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Thanks!

BTW, the first one doesn't compile because it's not a QString but a byte array, but still, is it better to create a variable for each step or to combine?

~codeslicer