279. Perfect Squares
Medium
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.
Constraints:
1 <= n <= 10^4
func numSquares(n int) int {
dp := make([]int, n + 1)
dp[0] = 0
dp[1] = 1
for i := 2; i <= n; i++ {
dp[i] = math.MaxInt32
for j := 1; i - j * j >= 0; j++ {
dp[i] = min(dp[i], dp[i - j * j] + 1)
}
}
return dp[n]
}
func min(a, b int) int {
if a < b { return a }
return b
}
Last modified 6mo ago