#P5308. I Wanna Become A 24-Point Master
I Wanna Become A 24-Point Master
Problem Description
Recently Rikka falls in love with an old but interesting game -- 24 points. She wants to become a master of this game, so she asks Yuta to give her some problems to practice.
Quickly, Rikka solved almost all of the problems but the remained one is really difficult:
In this problem, you need to write a program which can get 24 points with $n$ numbers, which are all equal to $n$.
Input
There are no more then 100 testcases and there are no more then 5 testcases with $n \geq 100$. Each testcase contains only one integer $n\ (1 \leq n \leq 10^5)$
Output
For each testcase:
If there is not any way to get 24 points, print a single line with -1.
Otherwise, let $A$ be an array with $2n-1$ numbers and at firsrt $A_i=n\ (1 \leq i \leq n)$. You need to print $n-1$ lines and the $i$th line contains one integer $a$, one char $b$ and then one integer c, where $1 \leq a,c <n+i$ and $b$ is "+","-","*" or "/". This line means that you let $A_a$ and $A_c$ do the operation $b$ and store the answer into $A_{n+i}$.
If your answer satisfies the following rule, we think your answer is right:
1. $A_{2n-1}=24$
2. Each position of the array $A$ is used at most one tine.
3. The absolute value of the numerator and denominator of each element in array $A$ is no more than $10^9$
4
1 * 2
5 + 3
6 + 4
Author
XJZX