Sha256: 1924990583419dde0b82a041f8312847d14b951fae5c7ba45919ebeae735632a
Contents?: true
Size: 1018 Bytes
Versions: 122
Compression:
Stored size: 1018 Bytes
Contents
package palindrome
import (
"fmt"
"strconv"
)
func isPal(x int) bool {
s := strconv.Itoa(x)
for i, j := 0, len(s)-1; i < j; i, j = i+1, j-1 {
if s[i] != s[j] {
return false
}
}
return true
}
type Product struct {
Product int
Factorizations [][2]int
}
func Products(fmin, fmax int) (pmin, pmax Product, err error) {
if fmin > fmax {
err = fmt.Errorf("fmin > fmax: %d > %d", fmin, fmax)
return
}
for x := fmin; x <= fmax; x++ {
for y := x; y <= fmax; y++ {
p := x * y
if !isPal(p) {
continue
}
compare := func(current *Product, better bool) {
switch {
case current.Factorizations == nil || better:
*current = Product{p, [][2]int{{x, y}}}
case p == current.Product:
current.Factorizations =
append(current.Factorizations, [2]int{x, y})
}
}
compare(&pmin, p < pmin.Product)
compare(&pmax, p > pmax.Product)
}
}
if len(pmin.Factorizations) == 0 {
err = fmt.Errorf("no palindromes in range [%d, %d]", fmin, fmax)
}
return
}
Version data entries
122 entries across 122 versions & 1 rubygems