A11188. Maximum splitting
编程题
普及/提高-
知识点
题目描述
You are given several queries. In the $i$ -th query you are given a single positive integer $n_{i}$ . You are to represent $n_{i}$ as a sum of maximum possible number of composite summands and print this maximum number, or print -1, if there are no such splittings.
An integer greater than $1$ is composite, if it is not prime, i.e. if it has positive divisors not equal to $1$ and the integer itself.
An integer greater than $1$ is composite, if it is not prime, i.e. if it has positive divisors not equal to $1$ and the integer itself.
输入格式
The first line contains single integer $q$ ( $1<=q<=10^{5}$ ) — the number of queries.
$q$ lines follow. The ( $i+1$ )-th line contains single integer $n_{i}$ ( $1<=n_{i}<=10^{9}$ ) — the $i$ -th query.
$q$ lines follow. The ( $i+1$ )-th line contains single integer $n_{i}$ ( $1<=n_{i}<=10^{9}$ ) — the $i$ -th query.
输出格式
For each query print the maximum possible number of summands in a valid splitting to composite summands, or -1, if there are no such splittings.
输入输出样例
输入 #1
1 12
输出 #1
3
输入 #2
2 6 8
输出 #2
1 2
输入 #3
3 1 2 3
输出 #3
-1 -1 -1
说明/提示
$12=4+4+4=4+8=6+6=12$ , but the first splitting has the maximum possible number of summands.
$8=4+4$ , $6$ can't be split into several composite summands.
$1,2,3$ are less than any composite number, so they do not have valid splittings.
$8=4+4$ , $6$ can't be split into several composite summands.
$1,2,3$ are less than any composite number, so they do not have valid splittings.