Sword finger offer 14- ii Cut rope II

The finger of the sword Offer 14- II. Cut the rope II

Medium difficulty 189
I'll give you a length of n The rope of , Please cut the rope to the whole length m paragraph （m、n Are integers. ,n>1 also m>1）, The length of each rope is recorded as k[0],k[1]…k[m - 1] . Excuse me, k[0]k[1]…*k[m - 1] What's the maximum possible product ？ for example , When the length of the rope is 8 when , We cut it into lengths of 2、3、3 Three paragraphs of , The maximum product we get here is 18.
The answer needs to be modelled 1e9+7（1000000007）, If the initial result of calculation is ：1000000008, Please return 1.

 Example  1：
 Input : 2 Output : 1 explain : 2 = 1 + 1, 1 × 1 = 1
 Example  2:
 Input : 10 Output : 36 explain : 10 = 3 + 3 + 4, 3 × 3 × 4 = 36

Tips ：

• 2 <= n <= 1000

Ideas

• The remainder of large numbers =》 Dynamic programming cannot be used =》 After taking the surplus max Functions cannot be used to compare sizes
• The finger of the sword Offer 14- I. Cut the rope Print the results
• Sum up the law
  

Code

class Solution {
    
public:
    int cuttingRope(int n) {
    
        long res=1;
        if(n==1||n==2)  return 1;
        else if(n==3)   return 2;
        // Disassemble into several 3
        while(n/3>1){
    
            res*=3;
            res%=1000000007;
            n-=3;
        }
        if(n%3==1)  res*=4;
        else res=res*3*(n%3?n%3:1);
        return res%1000000007;
    }
};