28 lines
621 B
Tcl
28 lines
621 B
Tcl
proc generate {n} {
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if {!$n} return
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set l [lrepeat $n "\[" "\]"]
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set len [llength $l]
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while {$len} {
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set tmp [lindex $l [set i [expr {int($len * rand())}]]]
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lset l $i [lindex $l [incr len -1]]
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lset l $len $tmp
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}
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return [join $l ""]
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}
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proc balanced s {
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set n 0
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foreach c [split $s ""] {
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# Everything unmatched is ignored, which is what we want
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switch -exact -- $c {
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"\[" {incr n}
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"\]" {if {[incr n -1] < 0} {return false}}
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}
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}
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expr {!$n}
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}
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for {set i 0} {$i < 15} {incr i} {
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set s [generate $i]
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puts "\"$s\"\t-> [expr {[balanced $s] ? {OK} : {NOT OK}}]"
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}
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