RosettaCodeData/Task/Zig-zag-matrix/Tcl/zig-zag-matrix.tcl
Ingy döt Net 68f8f3e56b all tasks
2013-04-11 01:07:29 -07:00

36 lines
761 B
Tcl

proc zigzag {size} {
set m [lrepeat $size [lrepeat $size .]]
set x 0; set dx -1
set y 0; set dy 1
for {set i 0} {$i < $size ** 2} {incr i} {
if {$x >= $size} {
incr x -1
incr y 2
negate dx dy
} elseif {$y >= $size} {
incr x 2
incr y -1
negate dx dy
} elseif {$x < 0 && $y >= 0} {
incr x
negate dx dy
} elseif {$x >= 0 && $y < 0} {
incr y
negate dx dy
}
lset m $x $y $i
incr x $dx
incr y $dy
}
return $m
}
proc negate {args} {
foreach varname $args {
upvar 1 $varname var
set var [expr {-1 * $var}]
}
}
print_matrix [zigzag 5]