Evaluate Addition Equation

You are given a mathematical expression represented as a string. The expression consists of one or more non-negative integers separated by the addition operator '+'. Your task is to compute the sum of these integers.

If the input string is empty, the result should be 0.

The mathematical formulation is as follows:

\(S = \sum_{i=1}^{n} a_i\)

where each \(a_i\) (for \(1 \leq i \leq n\)) is a non-negative integer.

inputFormat

The input consists of a single line containing the equation as a string. The equation is a sequence of digits and '+' operators without any spaces. For example: 3+5+8 or simply 5.

outputFormat

Output a single integer representing the sum of the numbers in the equation.

3+5+8

16