Given an integer n, return the least number of perfect square numbers that sum to n.
A perfect square is an integer that is the square of an integer; in other words, it is the product of some integer with itself. For example, 1, 4, 9, and 16 are perfect squares while 3 and 11 are not.
Example 1:
Input: n = 12
Output: 3
Explanation: 12 = 4 + 4 + 4.
Example 2:
Input: n = 13
Output: 2
Explanation: 13 = 4 + 9.
不要想复杂
class Solution:
def numSquares(self, n: int) -> int:
dp = [i for i in range(n+1)]
for i in range(1, n+1):
j = 1
while (j*j <= i):
dp[i] = min(dp[i], dp[i-j*j]+1)
j+=1
return dp[n]
s = Solution()
print(s.numSquares(13))
print(s.numSquares(12))