WRITING PART OF TEST $2$

You CANNOT log in the Programming Website before you submit your Writing Part $($we will see the log to detect this$)$

How to SUBMIT: You must hand$-$write your solution and and hand submit to the TA$/$instructor in the classroom.

Website you submit your written solution, log in the Programming there.

PROBLEM DESCRIPTION: Write a program to implement the following requirement:

stdin: a list of digits $x_1,x_2,$dots,$x_n$ separated by a comma $\text{'},\text{'}$ stdout: the SUM of these digits. If stdin is empty, print nothing.

A digit is $0$ or $1$ or $2,$dots, or $9.$ The number $n$ of digits is not given, but always in the range $0,10.$ You can only use getchar$(),$ putchar$(),$ and printf$()$ to work with stdin and stdout.

SAMPLE INTPUT $1$

$5,3,1,4$

SAMPLE OUTPUT $1$

$13$

SAMPLE INTPUT $2$

$5$

SAMPLE OUTPUT $2$

$5$