Rand () behavior in loop conditions

Question

I am trying to better understand the behavior of a loop containing some kind of rand () as its final condition. Consider the following example:

for(int i=0; i < rand()%6+10; i++) { do something }

In this case, the cycle will be repeated 10 to 15 times. My question is: will the completion value be evaluated once and then reused for the remaining iterations? or will it be reevaluated with each iteration?

Also, is this considered bad practice?

Answer 1

The condition is evaluated completely before each iteration. (Think about it: how does the compiler know which parts you want to evaluate each time, and which parts you don’t?)

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Answer 2

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{ for-init-statement while ( condition) { statement expression ; } }

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1 int r = rand() % N;

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1 int r = M + rand() % ( N - M );

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