Given a positive integer n, find the least number of perfect square numbers (for example, 1, 4, 9, 16, ...) which sum to n.
For example,
given *n* = 12, return 3 because 12 = 4 + 4 + 4;
given *n* = 13, return 2 because 13 = 4 + 9.
public class Solution {
public int numSquares(int n) {
int dp[] = new int[n+1];
dp[0] = 0;
for(int i = 1; i<=n; i++){
dp[i] = Integer.MAX_VALUE;
for(int j = 1; j*j<=i ;j++ ){
if(dp[i] > dp[i - j*j] + 1){
dp[i] = dp[i-j*j] + 1;
}
}
}
return dp[n];
}
}
