17 lines
616 B
Standard ML
17 lines
616 B
Standard ML
fun rowprint r = (List.app (fn i => print (StringCvt.padLeft #" " 3 (Int.toString i))) r;
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print "\n");
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fun zig lst M = List.app rowprint (lst M);
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fun sign t = if t mod 2 = 0 then ~1 else 1;
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fun zag n = List.tabulate (n,
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fn i=> rev ( List.tabulate (n,
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fn j =>
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let val t = n-j+i and u = n+j-i in
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if i <= j
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then t*t div 2 + sign t * ( t div 2 - i )
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else n*n - 1 - ( u*u div 2 + sign u * ( u div 2 - n + 1 + i) )
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end
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)));
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zig zag 5 ;
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