题目描述

Consider the set of all reduced fractions between $0$ and $1$ inclusive with denominators less than or equal to $N$.

Here is the set when $N = 5$:

$$\frac01,\frac15,\frac14,\frac13,\frac25,\frac12,\frac35,\frac23,\frac34 ,\frac45,\frac11$$

Write a program that, given an integer $N$ between $1$ and $160$ inclusive, prints the fractions in order of increasing magnitude.

输入格式

One line with a single integer $N$.

输出格式

One fraction per line, sorted in order of magnitude.

5

0/1
1/5
1/4
1/3
2/5
1/2
3/5
2/3
3/4
4/5
1/1

提示

USACO Training Section 2.1.