```go
package main

import (
	"fmt"
)

func main() {
	var n int
	if _, err := fmt.Scan(&n); err != nil {
		return
	}

	if n == 0 {
		fmt.Println(1)
		return
	}

	const mod = 1000003
	ans := 1
	for i := 0; i < n-1; i++ {
		ans = (ans * 3) % mod
	}
	fmt.Println(ans)
}
```