Score : $900$ points
Let $x$ be a string of length at least $1$.
We will call $x$ a good string, if for any string $y$ and any integer $k (k \geq 2)$, the string obtained by concatenating $k$ copies of $y$ is different from $x$.
For example, a, bbc and cdcdc are good strings, while aa, bbbb and cdcdcd are not.
Let $w$ be a string of length at least $1$. For a sequence $F=(\,f_1,\,f_2,\,...,\,f_m)$ consisting of $m$ elements, we will call $F$ a good representation of $w$, if the following conditions are both satisfied:
For example, when $w=$aabb, there are five good representations of $w$:
aabb$)$a$,$abb$)$aab$,$b$)$a$,$ab$,$b$)$a$,$a$,$b$,$b$)$Among the good representations of $w$, the ones with the smallest number of elements are called the best representations of $w$.
For example, there are only one best representation of $w=$aabb: $($aabb$)$.
You are given a string $w$. Find the following:
(It is guaranteed that a good representation of $w$ always exists.)
a-z).The input is given from Standard Input in the following format:
$w$
Print $2$ lines.
aab
1 1
bcbc
2 3
b$,$cbc$)$bc$,$bc$)$bcb$,$c$)$ddd
3 1