Problem:
Score : 200 points

Problem Statement

Find the sum of the integers between 1 and N (inclusive), whose sum of digits written in base 10 is between A and B (inclusive).

Constraints

1 \leq N \leq 10^4

1 \leq A \leq B \leq 36

All input values are integers.

Input

Input is given from Standard Input in the following format:

N A B

Output

Print the sum of the integers between 1 and N (inclusive), whose sum of digits written in base 10 is between A and B (inclusive).

Sample Input 1

20 2 5

Sample Output 1

84

Among the integers not greater than 20, the ones whose sums of digits are between 2 and 5, are: 2,3,4,5,11,12,13,14 and 20. We should print the sum of these, 84.

Sample Input 2

10 1 2

Sample Output 2

13

Sample Input 3

100 4 16

Sample Output 3

4554

Solution in Go (1.6) (judge verdict: Accepted)

package main
import (
   "fmt"
   "os"
   "bufio"
   "strconv"
)
var sc = bufio.NewScanner(os.Stdin)

func main() {
  sc.Split(bufio.ScanWords)
  n := nextInt()

  a := nextInt()
  b := nextInt()

  sum := 0
  for i := 1; i <= n; i++ {
	  if a <= i && i <= b && i < 10{
		sum = sum + i
	  } else {
		partSum := 0
        for _, v := range strconv.Itoa(i) {
         v, _ := strconv.Atoi(string(v))
         partSum = partSum + v
        }
	    if a <= partSum && partSum <= b {
		  sum = sum + i
		}
	  }
  }
  fmt.Println(sum)

}

func nextString() (string) {
	sc.Scan()
	v := sc.Text()
	return v
}

func nextInt() (int) {
	sc.Scan()
	v, e := strconv.Atoi(sc.Text())
    if e != nil { panic(e) }
    return v
}

func nextFloat() (float64) {
	sc.Scan()
	v, e := strconv.ParseFloat(sc.Text(), 64)
    if e != nil { panic(e) }
    return v
}