package main import ( "fmt" ) func main() { var d, n, o, u, u89 int64 for n = 1; n < 100000000; n++ { o = n for { u = 0 for { d = o%10 o = (o - d) / 10 u += d*d if o == 0 { break } } if u == 89 || u == 1 { if u == 89 { u89++ } break } o = u } } fmt.Println(u89) }