D - Maximum splitting

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You are given several queries. In the i-th query you are given a single positive integer ni. You are to represent ni 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.

Input

The first line contains single integer q (1 ≤ q ≤ 105) — the number of queries.

q lines follow. The (i + 1)-th line contains single integer ni (1 ≤ ni ≤ 109) — thei-th query.

Output

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.

Example
Input
1
12
Output
3
Input
2
6
8
Output
1
2
Input
3
1
2
3
Output
-1
-1
-1
Note

12 = 4 + 4 + 4 = 4 + 8 = 6 + 6 = 12, but the first splitting has the maximum possible number of summands.

8 = 4 + 46 can't be split into several composite summands.

1, 2, 3 are less than any composite number, so they do not have valid splittings.



代码

#include<cstdio>
#include<algorithm>
using namespace std;
int main()
{
	int n,m;
    while(scanf("%d",&n)!=EOF)
    {
    	while(n--)
    	{
    		scanf("%d",&m);
    		if(m<=3||m==5||m==7||m==11)
    		printf("-1\n");
    		else
    		{
    			int ans=m/4;
    			if((m%4)%2)
				ans--;
				printf("%d\n",ans); 
			}
		}
	}
return 0;
}
















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转载自blog.csdn.net/d1183/article/details/78409101