Multiple conditions in a C 'for' loop

Question

I came across this piece of code. I generally use \'&&\' or \'||\' to separate multiple conditions in a for loop, but this code uses commas to do that.<

Answer 1

The comma expression takes on the value of the last (eg. right-most) expression.

So in your first loop, the only controlling expression is i<=5; and j>=0 is ignored.

In the second loop, j>=0 controls the loop, and i<=5 is ignored.

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As for a reason... there is no reason. This code is just wrong. The first part of the comma-expressions does nothing except confuse programmers. If a serious programmer wrote this, they should be ashamed of themselves and have their keyboard revoked.