professional code quick tip

hy guys this night I'm quite tired I need a little tip ok var n could be from 0 to 12 var f must be set f=1 if 0<n<=4 f=2 if 5<n<=7 f=3 if 8<n<=12 f=4 if n>12 due to my fatigue I coded four if-if else statement, in other languages it is possible use conditional epression in switch case like switch $n case (0<n<=4): ........ but no in php any suggestion for more professional coding then 4 if/else statement tia a.g.