mirror of
https://github.com/cubixle/codekata-golang.git
synced 2026-04-24 22:44:44 +01:00
47 lines
915 B
Go
47 lines
915 B
Go
package main
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import (
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"fmt"
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"math/big"
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"strconv"
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)
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func main() {
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result := 0
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limit, _ := (&big.Int{}).SetString("1000000", 0)
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nLimit := 100
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for i := 1; i <= nLimit; i++ {
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for j := 0; j <= i; j++ {
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bi, _ := (&big.Int{}).SetString(strconv.Itoa(i), 0)
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fi := factorialOf(bi)
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bj, _ := (&big.Int{}).SetString(strconv.Itoa(j), 0)
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fj := factorialOf(bj)
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bk, _ := (&big.Int{}).SetString(strconv.Itoa(i-j), 0)
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fk := factorialOf(bk)
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mik := fj.Mul(fj, fk)
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dvk := mik.Div(fi, mik)
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if x := dvk.Add(dvk, limit.Neg(limit)); x.Int64() >= 0 {
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result++
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}
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}
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}
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fmt.Println(result)
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}
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func factorialOf(n *big.Int) *big.Int {
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one, _ := (&big.Int{}).SetString("1", 0)
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if n.Int64() <= 2 {
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return one
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}
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p, _ := (&big.Int{}).SetString("1", 0)
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i, _ := (&big.Int{}).SetString("2", 0)
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for {
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p = p.Mul(p, i)
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if i.String() == n.String() {
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break
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}
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i = i.Add(i, one)
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}
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return p
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}
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