剑指 Offer 14- II. 剪绳子 II

题目

剑指 Offer 14- II. 剪绳子 II

代码

class Solution {
public:
    int cuttingRope(int n) {
        if(n <= 3)
            return 1 * (n - 1);
        long res = 1;
        if(n % 3 == 1)
            res = 4, n -= 4;
        else if( n % 3 == 2)
            res = 2, n -= 2;
        while(n)
            res *= 3, res %= 1000000007, n -= 3;
        return res;
    }
};