Sasha and Ira are two best friends. But they aren't just friends, they are software engineers and experts in artificial intelligence. They are developing an algorithm for two bots playing a two-player game. The game is cooperative and turn based. In each turn, one of the players makes a move (it doesn't matter which player).
Algorithm for bots that Sasha and Ira are developing works by keeping track of the state the game is in. Each time either bot makes a move, the state changes. And, since the game is very dynamic, it will never go back to the state it was already in at any point in the past.
Sasha and Ira are perfectionists and want their algorithm to have an optimal winning strategy. They have noticed that in the optimal winning strategy, both bots make exactly
They are worried about the efficiency of their algorithm and are wondering what is the total number of states of the game that need to be analyzed?
Input Specification
The first and only line contains integer
Output Specification
Output should contain a single integer – number of possible states modulo
Constraints
Sample Input
2
Sample Output
19
Explanation
Start: Game is in state
Turn
Turn
Turn
Turn 4: Red bot already did
Overall, there are
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