Pell's equation: Difference between revisions

(3 intermediate revisions by the same user not shown)
Line 1,070:
=={{header|langur}}==
{{trans|D}}
<syntaxhighlight lang="langur">val .fun = ffn(.a, .b, .c) { [.b, .b x* .c + .a] }
 
val .solvePell = ffn(.n) {
val .x = trunc .n ^/ 2
var .y, .z, .r = .x, 1, .x x* 2
var .e1, .e2, .f1, .f2 = 1, 0, 0, 1
 
for {
.y = .r x* .z - .y
.z = (.n - .y x* .y) \ .z
.r = (.x + .y) \ .z
.e1, .e2 = .fun(.e1, .e2, .r)
.f1, .f2 = .fun(.f1, .f2, .r)
val .b, .a = .fun(.e2, .f2, .x)
if .a^2 - .n x* .b^2 == 1: return [.a, .b]
}
}
 
val .C = ffn(.x) {
# format number string with commas
var .neg, .s = "", toStringstring .x
if .s[1] == '-' {
.neg, .s = "-", rest .s
Line 1,099:
for .n in [61, 109, 181, 277, 8941] {
val .x, .y = .solvePell(.n)
writeln $"x² - \.n;y² = 1 for:\n\tx = \.x:.fn C;\n\ty = \.y:.fn C;\n"
}
}</syntaxhighlight>
 
{{out}}
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