For problem statement at 0-999/300-399/310-319/319/problemA.txt this is a correct solution, but verifier at 0-999/300-399/310-319/319/verifierA.go ends with All tests passed can you fix the verifier? ```go
package main

import (
	"bufio"
	"fmt"
	"os"
)

const mod = 1000000007

func main() {
	scanner := bufio.NewScanner(os.Stdin)
	scanner.Scan()
	x := scanner.Text()
	
	n := len(x)
	
	val := 0
	for i := 0; i < n; i++ {
		val = (val*2 + int(x[i]-'0')) % mod
	}
	
	p := 1
	for i := 0; i < n-1; i++ {
		p = (p * 2) % mod
	}
	
	fmt.Println((val * p) % mod)
}
```