Write a program that reads a sequence of integer numbers and prints how many of them are equal to the sum of all the elements which are behind them.

**Input**

Input is a sequence of integer numbers.

**Output**

In a line, print the number of integer numbers of the input sequence that are equal to the sum of all the elements which are behind them.

**Observation**

Use recursion (not tables).

Public test cases

**Input**

-34 11 7 2 -8 5 3 2

**Output**

3

**Input**

4 2 2 0

**Output**

3

**Input**

**Output**

0

**Input**

0 32 -16 -8 -4 -2 -2

**Output**

5

**Input**

28 32 -5 9

**Output**

0

Information

- Author
- Jordi Petit
- Language
- English
- Translator
- Carlos Molina
- Original language
- Catalan
- Other languages
- Catalan
- Official solutions
- C++
- User solutions
- C++ Python