Write a program to read the number of rows ($r$) and columns ($c$) of a two-dimensional integer array first, then read the array elements row by row. Finally print the average (in integer) of every column.
Both $r$ and $c$ are no more than $100$.
There are $r + 1$ lines in the input. The first line has $r$ and $c$. Each of the next $r$ lines has $c$ integers as a row in the matrix.
There are $c$ lines in the output. The $i$-th line has the average of the $i$-th column.
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