#MTH000000020. Hàm f91 (f91)

Hàm f91 (f91)

f91

Source: UVa

Version: Phuoc Hung OJ Extended

Problem Statement

McCarthy's recursive function f91f91 is defined for positive integers NN by

$$f91(N)= \begin{cases} f91(f91(N+11)), & N\le100,\\ N-10, & N\ge101. \end{cases}$$

Compute f91(N)f91(N).

Input

One positive integer NN.

Output

Print exactly

f91(N) = value

where N is replaced by the input value and value is f91(N)f91(N).

Subtasks

  • Subtask 1 (20%): 1≤N≤1001\le N\le100.
  • Subtask 2 (30%): 101≤N≤10000101\le N\le10000.
  • Subtask 3 (50%): Full constraints: 1≤N≤10000001\le N\le1000000.

Examples

Input

500

Output

f91(500) = 490

Explanation

Here N=500N=500, and 500≥101500\ge101, so the second branch of the definition applies. Thus

f91(500)=500−10=490.f91(500)=500-10=490.

Using the required output format, the program prints f91(500) = 490.