Count all possible paths from top left to bottom right of a mXn matrix | Returns count of possible paths to reach cell at row number m and column number n from the topmost leftmost cell ( cell at 1 , 1 ) ; If either given row number is first or given column number is first ; If diagonal movements are allowed then the last addition is required . ; Driver Code
< ? php function numberOfPaths ( $ m , $ n ) { if ( $ m == 1 $ n == 1 ) return 1 ; return numberOfPaths ( $ m - 1 , $ n ) + numberOfPaths ( $ m , $ n - 1 ) ; } echo numberOfPaths ( 3 , 3 ) ; ? >