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Pell's equation: Difference between revisions

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Pell's equation (view source)

Revision as of 01:20, 11 May 2021

12,520 bytes added ,  3 years ago
m
→‎{{header|Phix}}: added syntax colouring the hard way
(Added Delphi example)
m (→‎{{header|Phix}}: added syntax colouring the hard way)
Line 945:
{{libheader|Phix/mpfr}}
This now ignores the nonsquare part of the task spec, returning {1,0}.
<!--<lang Phix>include mpfr.e(notonline)-->
<span style="color: #008080;">include</span> <span style="color: #7060A8;">mpfr</span><span style="color: #0000FF;">.</span><span style="color: #000000;">e</span>
 
procedure fun(mpz a,b,t, integer c)
<span style="color: #008080;">procedure</span> <span style="color: #000000;">fun</span><span style="color: #0000FF;">(</span><span style="color: #7060A8;">mpz</span> <span style="color: #000000;">a</span><span style="color: #0000FF;">,</span><span style="color: #000000;">b</span><span style="color: #0000FF;">,</span><span style="color: #000000;">t</span><span style="color: #0000FF;">,</span> <span style="color: #004080;">integer</span> <span style="color: #000000;">c</span><span style="color: #0000FF;">)</span>
<span style="color: #000080;font-style:italic;">-- {a,b} = {b,c*b+a} (and t gets trashed)</span>
mpz_set(t,a)
<span style="color: #7060A8;">mpz_set</span><span style="color: #0000FF;">(</span><span style="color: #000000;">t</span><span style="color: #0000FF;">,</span><span style="color: #000000;">a</span><span style="color: #0000FF;">)</span>
mpz_set(a,b)
<span style="color: #7060A8;">mpz_set</span><span style="color: #0000FF;">(</span><span style="color: #000000;">a</span><span style="color: #0000FF;">,</span><span style="color: #000000;">b</span><span style="color: #0000FF;">)</span>
mpz_mul_si(b,b,c)
<span style="color: #7060A8;">mpz_mul_si</span><span style="color: #0000FF;">(</span><span style="color: #000000;">b</span><span style="color: #0000FF;">,</span><span style="color: #000000;">b</span><span style="color: #0000FF;">,</span><span style="color: #000000;">c</span><span style="color: #0000FF;">)</span>
mpz_add(b,b,t)
<span style="color: #7060A8;">mpz_add</span><span style="color: #0000FF;">(</span><span style="color: #000000;">b</span><span style="color: #0000FF;">,</span><span style="color: #000000;">b</span><span style="color: #0000FF;">,</span><span style="color: #000000;">t</span><span style="color: #0000FF;">)</span>
end procedure
<span style="color: #008080;">end</span> <span style="color: #008080;">procedure</span>
 
function SolvePell(integer n)
<span style="color: #008080;">function</span> <span style="color: #000000;">SolvePell</span><span style="color: #0000FF;">(</span><span style="color: #004080;">integer</span> <span style="color: #000000;">n</span><span style="color: #0000FF;">)</span>
integer x = floor(sqrt(n)), y = x, z = 1, r = x*2
<span style="color: #004080;">integer</span> <span style="color: #000000;">x</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">floor</span><span style="color: #0000FF;">(</span><span style="color: #7060A8;">sqrt</span><span style="color: #0000FF;">(</span><span style="color: #000000;">n</span><span style="color: #0000FF;">)),</span> <span style="color: #000000;">y</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">x</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">z</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">1</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">r</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">x</span><span style="color: #0000FF;">*</span><span style="color: #000000;">2</span>
mpz e1 = mpz_init(1), e2 = mpz_init(),
<span style="color: #7060A8;">mpz</span> <span style="color: #000000;">e1</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">mpz_init</span><span style="color: #0000FF;">(</span><span style="color: #000000;">1</span><span style="color: #0000FF;">),</span> <span style="color: #000000;">e2</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">mpz_init</span><span style="color: #0000FF;">(),</span>
f1 = mpz_init(), f2 = mpz_init(1),
<span style="color: #000000;">f1</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">mpz_init</span><span style="color: #0000FF;">(),</span> <span style="color: #000000;">f2</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">mpz_init</span><span style="color: #0000FF;">(</span><span style="color: #000000;">1</span><span style="color: #0000FF;">),</span>
t = mpz_init(0), u = mpz_init(),
<span style="color: #000000;">t</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">mpz_init</span><span style="color: #0000FF;">(</span><span style="color: #000000;">0</span><span style="color: #0000FF;">),</span> <span style="color: #000000;">u</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">mpz_init</span><span style="color: #0000FF;">(),</span>
a = mpz_init(1), b = mpz_init(0)
<span style="color: #000000;">a</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">mpz_init</span><span style="color: #0000FF;">(</span><span style="color: #000000;">1</span><span style="color: #0000FF;">),</span> <span style="color: #000000;">b</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">mpz_init</span><span style="color: #0000FF;">(</span><span style="color: #000000;">0</span><span style="color: #0000FF;">)</span>
if x*x!=n then
<span style="color: #008080;">if</span> <span style="color: #000000;">x</span><span style="color: #0000FF;">*</span><span style="color: #000000;">x</span><span style="color: #0000FF;">!=</span><span style="color: #000000;">n</span> <span style="color: #008080;">then</span>
while mpz_cmp_si(t,1)!=0 do
<span style="color: #008080;">while</span> <span style="color: #7060A8;">mpz_cmp_si</span><span style="color: #0000FF;">(</span><span style="color: #000000;">t</span><span style="color: #0000FF;">,</span><span style="color: #000000;">1</span><span style="color: #0000FF;">)!=</span><span style="color: #000000;">0</span> <span style="color: #008080;">do</span>
y = r*z - y
<span style="color: #000000;">y</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">r</span><span style="color: #0000FF;">*</span><span style="color: #000000;">z</span> <span style="color: #0000FF;">-</span> <span style="color: #000000;">y</span>
z = floor((n-y*y)/z)
<span style="color: #000000;">z</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">floor</span><span style="color: #0000FF;">((</span><span style="color: #000000;">n</span><span style="color: #0000FF;">-</span><span style="color: #000000;">y</span><span style="color: #0000FF;">*</span><span style="color: #000000;">y</span><span style="color: #0000FF;">)/</span><span style="color: #000000;">z</span><span style="color: #0000FF;">)</span>
r = floor((x+y)/z)
<span style="color: #000000;">r</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">floor</span><span style="color: #0000FF;">((</span><span style="color: #000000;">x</span><span style="color: #0000FF;">+</span><span style="color: #000000;">y</span><span style="color: #0000FF;">)/</span><span style="color: #000000;">z</span><span style="color: #0000FF;">)</span>
fun(e1,e2,t,r) -- {e1,e2} = {e2,r*e2+e1}
<span style="color: #000000;">fun</span><span style="color: #0000FF;">(</span><span style="color: #000000;">e1</span><span style="color: #0000FF;">,</span><span style="color: #000000;">e2</span><span style="color: #0000FF;">,</span><span style="color: #000000;">t</span><span style="color: #0000FF;">,</span><span style="color: #000000;">r</span><span style="color: #0000FF;">)</span> <span style="color: #000080;font-style:italic;">-- {e1,e2} = {e2,r*e2+e1}</span>
fun(f1,f2,t,r) -- {f1,f2} = {f2,r*r2+f1}
<span style="color: #000000;">fun</span><span style="color: #0000FF;">(</span><span style="color: #000000;">f1</span><span style="color: #0000FF;">,</span><span style="color: #000000;">f2</span><span style="color: #0000FF;">,</span><span style="color: #000000;">t</span><span style="color: #0000FF;">,</span><span style="color: #000000;">r</span><span style="color: #0000FF;">)</span> <span style="color: #000080;font-style:italic;">-- {f1,f2} = {f2,r*r2+f1}</span>
mpz_set(a,f2)
<span style="color: #7060A8;">mpz_set</span><span style="color: #0000FF;">(</span><span style="color: #000000;">a</span><span style="color: #0000FF;">,</span><span style="color: #000000;">f2</span><span style="color: #0000FF;">)</span>
mpz_set(b,e2)
<span style="color: #7060A8;">mpz_set</span><span style="color: #0000FF;">(</span><span style="color: #000000;">b</span><span style="color: #0000FF;">,</span><span style="color: #000000;">e2</span><span style="color: #0000FF;">)</span>
fun(b,a,t,x) -- {b,a} = {f2,x*f2+e2}
<span style="color: #000000;">fun</span><span style="color: #0000FF;">(</span><span style="color: #000000;">b</span><span style="color: #0000FF;">,</span><span style="color: #000000;">a</span><span style="color: #0000FF;">,</span><span style="color: #000000;">t</span><span style="color: #0000FF;">,</span><span style="color: #000000;">x</span><span style="color: #0000FF;">)</span> <span style="color: #000080;font-style:italic;">-- {b,a} = {f2,x*f2+e2}</span>
mpz_mul(t,a,a)
<span style="color: #7060A8;">mpz_mul</span><span style="color: #0000FF;">(</span><span style="color: #000000;">t</span><span style="color: #0000FF;">,</span><span style="color: #000000;">a</span><span style="color: #0000FF;">,</span><span style="color: #000000;">a</span><span style="color: #0000FF;">)</span>
mpz_mul_si(u,b,n)
<span style="color: #7060A8;">mpz_mul_si</span><span style="color: #0000FF;">(</span><span style="color: #000000;">u</span><span style="color: #0000FF;">,</span><span style="color: #000000;">b</span><span style="color: #0000FF;">,</span><span style="color: #000000;">n</span><span style="color: #0000FF;">)</span>
mpz_mul(u,u,b)
<span style="color: #7060A8;">mpz_mul</span><span style="color: #0000FF;">(</span><span style="color: #000000;">u</span><span style="color: #0000FF;">,</span><span style="color: #000000;">u</span><span style="color: #0000FF;">,</span><span style="color: #000000;">b</span><span style="color: #0000FF;">)</span>
mpz_sub(t,t,u) -- t = a^2-n*b^2
<span style="color: #7060A8;">mpz_sub</span><span style="color: #0000FF;">(</span><span style="color: #000000;">t</span><span style="color: #0000FF;">,</span><span style="color: #000000;">t</span><span style="color: #0000FF;">,</span><span style="color: #000000;">u</span><span style="color: #0000FF;">)</span> <span style="color: #000080;font-style:italic;">-- t = a^2-n*b^2</span>
end while
<span style="color: #008080;">end</span> <span style="color: #008080;">while</span>
end if
<span style="color: #008080;">end</span> <span style="color: #008080;">if</span>
return {a, b}
<span style="color: #008080;">return</span> <span style="color: #0000FF;">{</span><span style="color: #000000;">a</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">b</span><span style="color: #0000FF;">}</span>
end function
<span style="color: #008080;">end</span> <span style="color: #008080;">function</span>
sequence ns = {4, 61, 109, 181, 277, 8941}
<span style="color: #004080;">sequence</span> <span style="color: #000000;">ns</span> <span style="color: #0000FF;">=</span> <span style="color: #0000FF;">{</span><span style="color: #000000;">4</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">61</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">109</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">181</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">277</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">8941</span><span style="color: #0000FF;">}</span>
for i=1 to length(ns) do
<span style="color: #008080;">for</span> <span style="color: #000000;">i</span><span style="color: #0000FF;">=</span><span style="color: #000000;">1</span> <span style="color: #008080;">to</span> <span style="color: #7060A8;">length</span><span style="color: #0000FF;">(</span><span style="color: #000000;">ns</span><span style="color: #0000FF;">)</span> <span style="color: #008080;">do</span>
integer n = ns[i]
<span style="color: #004080;">integer</span> <span style="color: #000000;">n</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">ns</span><span style="color: #0000FF;">[</span><span style="color: #000000;">i</span><span style="color: #0000FF;">]</span>
mpz {x, y} = SolvePell(n)
<span style="color: #7060A8;">mpz</span> <span style="color: #0000FF;">{</span><span style="color: #000000;">x</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">y</span><span style="color: #0000FF;">}</span> <span style="color: #0000FF;">=</span> <span style="color: #000000;">SolvePell</span><span style="color: #0000FF;">(</span><span style="color: #000000;">n</span><span style="color: #0000FF;">)</span>
string xs = mpz_get_str(x,comma_fill:=true),
<span style="color: #004080;">string</span> <span style="color: #000000;">xs</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">mpz_get_str</span><span style="color: #0000FF;">(</span><span style="color: #000000;">x</span><span style="color: #0000FF;">,</span><span style="color: #000000;">comma_fill</span><span style="color: #0000FF;">:=</span><span style="color: #004600;">true</span><span style="color: #0000FF;">),</span>
ys = mpz_get_str(y,comma_fill:=true)
<span style="color: #000000;">ys</span> <span style="color: #0000FF;">=</span> <span style="color: #7060A8;">mpz_get_str</span><span style="color: #0000FF;">(</span><span style="color: #000000;">y</span><span style="color: #0000FF;">,</span><span style="color: #000000;">comma_fill</span><span style="color: #0000FF;">:=</span><span style="color: #004600;">true</span><span style="color: #0000FF;">)</span>
printf(1,"x^2 - %3d*y^2 = 1 for x = %27s and y = %25s\n", {n, xs, ys})
<span style="color: #7060A8;">printf</span><span style="color: #0000FF;">(</span><span style="color: #000000;">1</span><span style="color: #0000FF;">,</span><span style="color: #008000;">"x^2 - %3d*y^2 = 1 for x = %27s and y = %25s\n"</span><span style="color: #0000FF;">,</span> <span style="color: #0000FF;">{</span><span style="color: #000000;">n</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">xs</span><span style="color: #0000FF;">,</span> <span style="color: #000000;">ys</span><span style="color: #0000FF;">})</span>
end for</lang>▼
<span style="color: #008080;">end</span> <span style="color: #008080;">for</span>
▲end for<!--</lang>-->
{{out}}
<pre>
Petelomax
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