exercism/go/pythagorean-triplet/pythagorean.go

45 lines
871 B
Go
Raw Normal View History

2016-08-13 23:20:14 +00:00
package pythagorean
import "math"
// Triplet just holds three ints
type Triplet struct {
a, b, c int
}
// Range finds all pythagorean triplets
// from min to max
func Range(min, max int) []Triplet {
var ret []Triplet
for a := min; a <= max; a++ {
for b := a + 1; b <= max; b++ {
cSq := float64(a*a + b*b)
c := int(math.Sqrt(cSq))
if c >= min && c <= max && isTriplet(a, b, c) {
ret = append(ret, Triplet{a, b, c})
}
}
}
return ret
}
// Sum finds all triplets that sum up to total
func Sum(total int) []Triplet {
var ret []Triplet
// No side of a triangle can be over 1/2 of the total
for a := 1; a <= (total / 2); a++ {
for b := a; b <= (total / 2); b++ {
c := total - a - b
if isTriplet(a, b, c) {
ret = append(ret, Triplet{a, b, c})
}
}
}
return ret
}
func isTriplet(a, b, c int) bool {
return (a*a + b*b) == c*c
}