#P1925. 最大划分乘积

最大划分乘积

Description

Let NN be a positive integer and let NN be split into kk equal parts, r=N/kr = N/k, so that N=r+r+...+rN = r + r + ... + r.

Let PP be the product of these parts, P=r×r×...×r=rkP = r ×r × ... × r = rk.

For example, if 1111 is split into five equal parts, 11=2.2+2.2+2.2+2.2+2.211 = 2.2 + 2.2 + 2.2 + 2.2 + 2.2, then P=2.25=51.53632P = 2.2^5 = 51.53632.

Let M(N)=PmaxM(N) = P_{\max} for a given value of NN.

It turns out that the maximum for N=11N = 11 is found by splitting eleven into four equal parts which leads to Pmax=(11/4)4P_{max} = (11/4)^4; that is, M(11)=14641/256=57.19140625M(11) = 14641/256 = 57.19140625, which is a terminating decimal.

However, for N=8N = 8 the maximum is achieved by splitting it into three equal parts, so M(8)=512/27M(8) = 512/27, which is a non-terminating decimal.

Let D(N)=ND(N) = N if M(N)M(N) is a non-terminating decimal and D(N)=ND(N) = -N if M(N)M(N) is a terminating decimal.

Input Format

Input a positive integer a(5a32767)a(5≤a≤32767).

Output Format

Output the value of D(5)+D(6)+...+D(a)D(5)+D(6)+...+D(a).

10
-15
100
2438