$ go run main.go
Hello, playground
elapsed = 123
elapsed = 1001155630
elapsed = 999912495
elapsed = 999697280
elapsed = 1000283063
elapsed = 999257141
elapsed = 1000514965
elapsed = 1000064868
elapsed = 999972841
elapsed = 1000014802
elapsed = 998811397
elapsed = 1001099525
elapsed = 999153951