Problem five brute force solution

set num {1 2 3 4 5 6 7 8 9}
set correct {}

for { set i 0 } { $i < 3 ** ([llength $num] - 1) } { incr i } {
	set n $i
	set s {}
	set t $num
	while { [llength $t] > 0 } {
		append s [lindex $t 0]
		set t [lrange $t 1 end]
		switch -exact -- [expr { $n % 3 }] {
			0 {}
			1 { append s - }
			2 { append s + }
		}
		set n [expr { $n / 3 }]
	}
	if { [expr $s] == 100 } {
		lappend correct $s
	}
}
puts [llength $correct]\n\t[join $correct \n\t]