# [279\. Perfect Squares](https://leetcode.com/problems/perfect-squares/) :::spoiler ```cpp= class Solution { public: int numSquares(int n) { vector<int> dp(n + 1, INT_MAX); dp[0] = 0; for (int i = 1; i <= n; i++) { for (int j = 1; j * j <= i; j++) { dp[i] = min(dp[i], dp[i - j * j] + 1); } } return dp[n]; } }; ``` - T: $O(N \cdot \sqrt{N})$ - S: $O(N)$ :::