CF628E Zbazi in Zeydabad

A tourist wants to visit country Zeydabad for Zbazi (a local game in Zeydabad). The country Zeydabad is a rectangular table consisting of $ n $ rows and $ m $ columns. Each cell on the country is either 'z' or '.'. The tourist knows this country is named Zeydabad because there are lots of ''Z-pattern"s in the country. A ''Z-pattern" is a square which anti-diagonal is completely filled with 'z' and its upper and lower rows are also completely filled with 'z'. All other cells of a square can be arbitrary. Note that a ''Z-pattern" can consist of only one cell (see the examples). So he wants to count the number of ''Z-pattern"s in the country (a necessary skill for Zbazi). Now your task is to help tourist with counting number of ''Z-pattern"s. As input/output can reach huge size it is recommended to use fast input/output methods: for example, prefer to use gets/scanf/printf instead of getline/cin/cout in C++, prefer to use BufferedReader/PrintWriter instead of Scanner/System.out in Java.

The first line contains two integers $ n,m $ ( $ 1

Print the only integer $ a $ — the number of ''Z-pattern"s in Zeydabad.