Pseudocode and Flowchart please.

Sum of Digits in a String

Design a program that asks the user to enter a string containing a series of single digit numbers with nothing separating them. The program should display the sum of all the single digit numbers in the string. For example, if the user enters $2514,$ the method should return $12,$ which is the sum of $2,5,1,$ and $4.($Hint: The stringToInteger library function can be used to convert a single character to an integer.$)$