Sum of Perfect Squares Matching Pattern

Problem Statement

Sum of Perfect Squares Matching Pattern Problem Description Sumit was cleaning his house and found an old book of math problems. On one of the pages was a set of numbers with some digits missing. Every missing digit had been written as an underscore ('_'). At the end of the page was a clue for filling in the missing digits - "All these numbers are perfect squares". Following the clue, Sumit wants the sum of all the perfect squares that match a given pattern P. Help him with a program that computes it. A number matches the pattern P when both of the following hold: the decimal representation of the number, written without leading zeros, has exactly as many digits as P has characters, and at every position where P holds a digit, the number holds that same digit. A position where P holds an underscore may hold any digit. A perfect square is a number of the form k x k for some integer k >= 0. Input Format A single line containing the pattern P. Output Format A single line containing the