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