Dyck path | Returns count Dyck paths in n x n grid ; Compute value of 2 nCn ; return 2 nCn / ( n + 1 ) ; Driver Code
function countDyckPaths ( n ) { let res = 1 ; for ( let i = 0 ; i < n ; ++ i ) { res *= ( 2 * n - i ) ; res /= ( i + 1 ) ; } return res / ( n + 1 ) ; } let n = 4 ; document . write ( " " + countDyckPaths ( n ) ) ;