A rectangular field of size *m*× *n* contains *mn* square areas. Some of
the areas are occupied by a determinated growing (tomatoes, carrots, etc.)
that is identified by a natural number strictly positive. It is known that growings
are grouped in different disjointed rectangles and that a growing always is
separated of another one by areas without grownings, identify by the value 0.

Write a program that reads fields and prints the number of rectangular growings.

**Input**

Input consists in a sequence of fields. For each field, it is given two natural
numbers *m* and *n* with *m*≥1 and *n*≥1 that represent the size of the field.
Then, it is given *m* rows, each one with *n* natural numbers that represent
the growing of the area. The fields follow the hypotheses described previously.

**Output**

For each fielf of the input, print in a line the number of rectangular growings.

Public test cases

**Input**

6 10 1 1 1 0 3 3 3 0 2 2 1 1 1 0 3 3 3 0 2 2 0 0 0 0 3 3 3 0 0 0 2 2 0 0 3 3 3 0 4 4 0 0 0 0 0 0 0 0 0 0 1 1 1 1 1 0 4 4 4 0 3 3 0 0 0 0 9 0 0 0 0

**Output**

7 1

Information

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