/
main.go
78 lines (60 loc) · 1.31 KB
/
main.go
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package main
import (
"log"
"os"
"strconv"
"github.com/TomasCruz/projecteuler"
)
/*
Problem 52; Permuted multiples
It can be seen that the number, 125874, and its double, 251748, contain exactly the same digits,
but in a different order.
Find the smallest positive integer, x, such that 2x, 3x, 4x, 5x, and 6x, contain the same digits.
*/
func main() {
var limit int
if len(os.Args) > 1 {
limit64, err := strconv.ParseInt(os.Args[1], 10, 64)
if err != nil {
log.Fatal("bad argument")
}
limit = int(limit64)
} else {
limit = 1000000
}
projecteuler.Timed(calc, limit)
}
func calc(args ...interface{}) (result string, err error) {
limit := args[0].(int)
for i := 1; i < limit; i++ {
if checkNumber(i) {
result = strconv.FormatInt(int64(i), 10)
break
}
}
return
}
func checkNumber(x int) bool {
dn := projecteuler.NewDigitalNumber(x)
d2 := projecteuler.NewDigitalNumber(2 * x)
if !dn.SameDigitSet(d2) {
return false
}
d3 := projecteuler.NewDigitalNumber(3 * x)
if !dn.SameDigitSet(d3) {
return false
}
d4 := projecteuler.NewDigitalNumber(4 * x)
if !dn.SameDigitSet(d4) {
return false
}
d5 := projecteuler.NewDigitalNumber(5 * x)
if !dn.SameDigitSet(d5) {
return false
}
d6 := projecteuler.NewDigitalNumber(6 * x)
if !dn.SameDigitSet(d6) {
return false
}
return true
}