Elpezmuerto
Reputation: 5571
If block vs Switch-Case block
Generally is there a performance difference between using an if block with many else ifs compared to a switch case block? Do some languages or style conventions prefer one over the other?
Specifically I am curious about Matlab, C, and C++
Upvotes: 5
Views: 1320
Answers (2)
Michael Goldshteyn
Reputation: 74340
A switch can be optimized by the compiler, in some cases, into a lookup table and branch. This could be considerably faster than multiple if/else-ifs.
Upvotes: 3
Lou Franco
Reputation: 89152
In C, the optimizer can turn a switch into a calculated jmp, so it can be faster. This is possible because you always switch on an integer constant.
Upvotes: 1
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