package main func main() { c := make(chan int, 1) for range 3 { select { default: println(1) case <-c: println(2) case c <- 1: println(3) } } }

This Go code creates a buffered channel c with a buffer size of 1 and runs a loop of 3 iterations, each executing a select statement with three cases:

• default: prints 1
• receiving from channel c: prints 2
• sending the value 1 into channel c: prints 3

Let's analyze the behavior per iteration:

1. The channel is empty, the buffer is empty, and sending to the channel is possible — the case c <- 1 executes, printing 3.
2. Now the channel has one value (buffer is full), sending is not possible, but receiving is — the case <-c executes, printing 2.
3. The channel is empty again, sending is possible — it prints 3.

Final output:

3
2
3

Thus, the program demonstrates working with a buffered channel and choosing between sending, receiving, and the default case in select.