Speed of execution in term of code in some cases

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Is “else if” faster than “switch() case”?


For small loops not required,For very big loop hash table is used for  switch case so faster execution.
But with good compiler with optimization enabled, it's same.


Why i++ is faster than i=i+1 in c


older compilers used 
(1)ADD      \\i+1
(2)Assignment operation          \i=x
for i=i+1

for i++
(1)INR

but currently good compilers with optimizations enabled creates same assembly code.


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