This is a problem from a training contest of the UPC Programming Conest<http://concurs.lsi.upc.edu/> .
I have been thinking of it a lot and I can't find the solution. Any ideas? In the game of chess, a pawn is a piece that only threatens two squares, namely the two diagonally in front of it (if these squares exist). For instance, in this example board with five rows and seven columns, the pawn at c4 threatens b3 and d3, the pawn at a2 only threatens b1, the pawn at g5 only threatens f4, and the pawn at e1 threatens no square. (In a real chess game no pawn can appear at the first or last row, but we forget that rule here.) Now, given the number of rows *R* and the number of columns *C* of the board, can you compute *Pawns(R, C)*, the number of ways to place *R* pawns in the board such that all the pawns but one threatens exactly another pawn and all the pawns but one is threatened exactly by another pawn? InputEach line of input has two integers *R* (1 ≤ *R* ≤ 50) and *C* (1 ≤ *C*≤ 50) with the dimensions of the board. OutputFor each input line, print a line with *R*, *C* and *Pawns(R, C)*. You can assume that the decimal representation of *Pawns(R, C)* requires less than 18 digits. Sample Input 1 9 4 2 5 7 Sample Output 1 9 9 4 2 2 5 7 74 *Author:* Salvador Roura Thanks, Albert -- OuFeRRaT http://ouferrat.blogspot.com/ --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Algorithm Geeks" group. To post to this group, send email to algogeeks@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/algogeeks -~----------~----~----~----~------~----~------~--~---
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