使用uint64的for循环不会停止

Question

Is there an explanation why for loop using uint64 wouldn't stop at 0?

I've tried the same for loop with int and it works as expected.

package main

import (
    "fmt"
)

func main() {
  i := uint64(5)
  for ; i>=uint64(0); i-- {
  fmt.Printf("step %d
", i)
  }
}

I would expect this function to stop at output step 0 but it overflows the int and continues forever with step 18446744073709551615 and so on

Answer 1

Your loop continues while i >= 0, but an unsigned integer is always greater than or equal to zero. Unsigned integers cannot be negative so your loop never terminates.

Try changing i to int64 and see if it behaves differently. :-)

Best of luck.