# Find the minimum number of squares that sum of them equal to a given number in Java

16 views
edited Nov 23

```public class MyClass {
public static boolean isPerfectSquare(int n) {
double sqr = Math.sqrt(n);

return sqr == Math.floor(sqr);
}
public static int findMinSquares(int n)
{
if (isPerfectSquare(n)) {
return 1;
}

int squares = n;

for (int i = 1; i * i < n; i++) {
squares = Integer.min(squares, 1 + findMinSquares(n - i * i));
}

return squares;
}

public static void main(String args[]) {
int n = 63; // 63 = 7*7(49) + 3*3(9) + 2*2(4) + 1*1(1) // 4 number of squares
System.out.println("The minimum number of squares: " + findMinSquares(n));

n = 23; // 23 = 3*3(9) + 3*3(9) + 2*2(4) + 1*1(1) // 4 number of squares
System.out.println("The minimum number of squares: " + findMinSquares(n));

n = 100; // 100 = 10*10(100) // 1 number of squares
System.out.println("The minimum number of squares: " + findMinSquares(n));

}
}

/*
run:

The minimum number of squares: 4
The minimum number of squares: 4
The minimum number of squares: 1

*/```