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The sieve of eratosthenes

TCL

#!/usr/bin/tclsh
#Sieve of Eratosthenes in TCL
# by Ted Mierzwinski

proc printList nums {
        set val 0
        foreach i $nums {
                if {$i == 1} {puts -nonewline "$val "}
                incr val
        }
        puts "\b"
}

proc removeMultiples {nums mult max} {
        for {set i [expr $mult*$mult]} {$i <= $max} {set i [expr $i + $mult]} {
                lset nums [expr $i] 0
        }
        return $nums
}

proc nextPrime {nums prev max} {
        for {set i [expr $prev + 1]} {$i <= $max} {incr i} {
                if {[lindex $nums $i] == 1} { return $i }
        }
        return -1
}

if {$argc == 0} {
        return
}

set max [lindex $argv 0]

set nums {0 0}
for {set i 2} {$i <= $max} {incr i} {
        lappend nums 1
}

set p 2

while {$p != -1} {
        set nums [removeMultiples $nums $p $max]
        set p [nextPrime $nums $p $max]
}

printList $nums

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