Language: Go

Source code:

package main import "fmt" import "time" import "encoding/binary" func test1 (truba1 chan uint64,truba3 chan uint64){ n1 := <- truba1 if n1*n1*n1*n1 - 333*n1*n1*n1 - 502852*n1*n1 + 32232192*n1 + 46093059072 == 0 { truba3 <- n1 }else{ truba3 <- 0 } } func test2 (truba2 chan uint64,truba3 chan uint64){ n2 := <- truba2 if n2*n2*n2*n2 - 259*n2*n2*n2 - 455274*n2*n2 - 50590424*n2 + 11117720960 == 0 { truba3 <- n2 }else{ truba3 <- 0 } } func test3 (truba3 chan uint64){ var wow uint64 = 0 for n:=0; n<2;n++{ lol := <- truba3 if lol % 2 !=0 { wow += lol } } truba3 <- wow } func main (){ var tvoe_chislo1 uint64 var tvoe_chislo2 uint64 fmt.Print("Enter serial: ") fmt.Scanf("%d-%d",&tvoe_chislo1,&tvoe_chislo2) truba1 := make(chan uint64,2) truba2 := make(chan uint64,2) truba3 := make(chan uint64,2) go test1(truba1,truba3) go test2(truba2,truba3) go test3(truba3) truba1 <- tvoe_chislo1 truba2 <- tvoe_chislo2 time.Sleep(time.Second * 1) res := <-truba3 if res > 0 { bs := make([]byte, 8) binary.BigEndian.PutUint64(bs,res*31337+54203286357058) fmt.Println("Flag{"+string(bs)+"}") }else{ fmt.Println("Wrong serail") } } // https://gobyexample.com/

Flag will be printed when you enter correct serial.

Compiled Linux binary: go_task
Compiled Windows binary: go_task.exe