Generate Pascal's Triangle

Given an integer N, generate the first N rows of Pascal's Triangle. Each element in the triangle is defined by the formula \(C(n,k) = \frac{n!}{k!(n-k)!}\). If \(N \le 0\), output nothing.

For example, when \(N=5\), the triangle is:

1
1 1
1 2 1
1 3 3 1
1 4 6 4 1

inputFormat

The input consists of a single integer N provided via STDIN, denoting the number of rows to generate.

outputFormat

Output the Pascal's Triangle rows, each row on a new line. Within a row, numbers are separated by a single space. If no rows are generated (i.e. when \(N \le 0\)), output nothing.

## sample

5

1
1 1
1 2 1
1 3 3 1
1 4 6 4 1

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