38 lines
632 B
Markdown
38 lines
632 B
Markdown
## 2.2 (Power)
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```Ocaml
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(*First version ; 6 multiplications*)
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# let power28(x) =
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let x2 = x + x in
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let x4 = x2*x2 in
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let x8 = x4*x4 in
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let x16 = x8*x8 in
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x16*x8*x4 ;;
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(*Second version ; 27 multiplications*)
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# let power28(x) = x*x*x*x*x*x...*x ;;
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(*Third version ; 11 multiplications*)
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# let power28(x) =
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let sq(x) = x*x in
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let pow4(x) = sq(sq(x)) in
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pow4(pow4(x))*sq(pow4(x))*pow4(x);;
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(*Fourth version ; 7 multiplications*)
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# let power28(x)=
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let sq(x) = x+x in
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let p4=sq(sq(x)) in
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sq(sq(p4))*sq(p4)*p4;;
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```
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## 2.3
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![[F1D2AA19-E790-4022-AFFF-F778EAB28AB5.jpg]]
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![[69E2987C-209A-48CD-8964-5A60462966E5.jpg]]
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