Class Solution


  • public class Solution
    extends Object
    391 - Perfect Rectangle.

    Hard

    Given an array rectangles where rectangles[i] = [xi, yi, ai, bi] represents an axis-aligned rectangle. The bottom-left point of the rectangle is (xi, yi) and the top-right point of it is (ai, bi).

    Return true if all the rectangles together form an exact cover of a rectangular region.

    Example 1:

    Input: rectangles = [[1,1,3,3],[3,1,4,2],[3,2,4,4],[1,3,2,4],[2,3,3,4]]

    Output: true

    Explanation: All 5 rectangles together form an exact cover of a rectangular region.

    Example 2:

    Input: rectangles = [[1,1,2,3],[1,3,2,4],[3,1,4,2],[3,2,4,4]]

    Output: false

    Explanation: Because there is a gap between the two rectangular regions.

    Example 3:

    Input: rectangles = [[1,1,3,3],[3,1,4,2],[1,3,2,4],[3,2,4,4]]

    Output: false

    Explanation: Because there is a gap in the top center.

    Example 4:

    Input: rectangles = [[1,1,3,3],[3,1,4,2],[1,3,2,4],[2,2,4,4]]

    Output: false

    Explanation: Because two of the rectangles overlap with each other.

    Constraints:

    • 1 <= rectangles.length <= 2 * 104
    • rectangles[i].length == 4
    • -105 <= xi, yi, ai, bi <= 105
    • Constructor Detail

      • Solution

        public Solution()
    • Method Detail

      • isRectangleCover

        public boolean isRectangleCover​(int[][] rectangles)