14 lines
251 B
Forth
14 lines
251 B
Forth
: lastn ( rows -- n ) dup 1- * 2/ ;
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: width ( n -- n ) s>f flog ftrunc f>s 2 + ;
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: triangle ( rows -- )
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dup lastn 0 rot ( last 0 rows )
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0 do
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over cr
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i 1+ 0 do
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1+ swap 1+ swap
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2dup width u.r
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loop
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drop
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loop
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2drop ;
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