Canadian Computing Competition: 2012 Stage 1, Senior #1
A CCC soccer game operates under slightly different soccer rules. A goal is only counted if the players, in order, who touched the ball prior to the goal have jersey numbers that are in strictly increasing numeric order with the highest number being the goal scorer.
Players have jerseys numbered from to (and each jersey number is worn by exactly one player).
Given a jersey number of the goal scorer, indicate how many possible combinations of players can produce a valid goal.
Input Specification
The input will be the positive integer (), which is the jersey number of the goal scorer.
Output Specification
The output will be one line containing the number of possible scoring combinations that could have as the goal scoring jersey number.
Sample Input 1
4
Output for Sample Input 1
1
Sample Input 2
2
Output for Sample Input 2
0
Sample Input 3
90
Output for Sample Input 3
113564
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