Problem Statement
Given the width and height of a rectangular grid, return the total number of rectangles (NOT counting squares) that can be found on this grid.
For example, width = 3, height = 3 (see diagram below):
__ __ __ |__|__|__| |__|__|__| |__|__|__|
In this grid, there are 4 2x3 rectangles, 6 1x3 rectangles and 12 1x2 rectangles. Thus there is a total of 4 + 6 + 12 = 22 rectangles. Note we don't count 1x1, 2x2 and 3x3 rectangles because they are squares.
Definition
- Class:
- RectangularGrid
- Method:
- countRectangles
- Parameters:
- int, int
- Returns:
- long
- Method signature:
- long countRectangles(int width, int height)
- (be sure your method is public)
Notes
- rectangles with equals sides (squares) should not be counted.
Constraints
- width and height will be between 1 and 1000 inclusive.
Examples
3
3
Returns: 22
See above5
2
Returns: 31
__ __ __ __ __ |__|__|__|__|__| |__|__|__|__|__| In this grid, there is one 2x5 rectangle, 2 2x4 rectangles, 2 1x5 rectangles, 3 2x3 rectangles, 4 1x4 rectangles, 6 1x3 rectangles and 13 1x2 rectangles. Thus there is a total of 1 + 2 + 2 + 3 + 4 + 6 + 13 = 31 rectangles.10
10
Returns: 2640
1
1
Returns: 0
592
964
Returns: 81508708664