279. 完全平方数

class Solution {
public:
    int numSquares(int n) {
        int * dp = new int[max(n + 1, 3)];

        dp[0] = 0;
        dp[1] = 1;
        dp[2] = 2;

        for (int i = 3; i <= n; i++)
        {
            int min = INT_MAX;
            for (int j = sqrt(i); j >= 1; j--)
            {
                int mm = dp[i - j * j] + 1;
                if (min > mm)
                {
                    min = mm;
                }
            }
            dp[i] = min;
        }

        return dp[n];
    }
   
};