Problem:
Score : 100 points

Problem Statement

Snuke has a grid consisting of three squares numbered 1, 2 and 3.
In each square, either 0 or 1 is written. The number written in Square i is s_i.

Snuke will place a marble on each square that says 1.
Find the number of squares on which Snuke will place a marble.

Constraints

Each of s_1, s_2 and s_3 is either 1 or 0.

Input

Input is given from Standard Input in the following format:

s_{1}s_{2}s_{3}

Output

Print the answer.

Sample Input 1

101

Sample Output 1

2

A marble will be placed on Square 1 and 3.

Sample Input 2

000

Sample Output 2

0

No marble will be placed on any square.

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

package main

import (
	"fmt"
	"strconv"
)

func main() {
	var s string
	fmt.Scan(&s)

	var s1 int
	var s2 int
	var s3 int

	s1, _ = strconv.Atoi(string(s[0]))
	s2, _ = strconv.Atoi(string(s[1]))
	s3, _ = strconv.Atoi(string(s[2]))
	fmt.Println(s1 + s2 + s3)

}