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# if...else...elseif at TCL
if [expr $cost > 100] {
set cost [expr $cost * 0.8]
puts "SPECIAL Group ticket at $cost"
} elseif [expr $cost > 20] {
set cost [expr $cost * 0.9]
puts "Group ticket at $cost"
} else {
puts "Total Price will be $cost"
}