package main

import (
    "fmt"
    "time"
)

func main() {
    go task(20000)
    go task(10000)
    time.Sleep(time.Second * 5)
    fmt.Println("End")
}

func task(count int64) {
    start := time.Now()
    for i := count; i > 0; i-- {
        for j := count; j > 0; j-- {
        }
    }
    end := time.Now()
    fmt.Printf("Count %d; %d.%d - %d.%d\n", count, start.Second(), start.Nanosecond(), end.Second(), end.Nanosecond())
}