513. 完美平方

class Solution:
    """
    @param n: a positive integer
    @return: An integer
    """
    ‘‘‘
    大致思路:
    1.划分型动态规划
    ‘‘‘
    def numSquares(self, n):

        #初始化
        dp = [sys.maxsize for _ in range(n + 1)] 
        dp[0] = 0

        for i in range(1,n + 1):
            for j in range(1,i + 1):
                if (i - j*j) >= 0:
                    dp[i] = min(dp[i], dp[i - j*j] + 1)
        
        return dp[n]