Class Solution


  • public class Solution
    extends Object
    1253 - Reconstruct a 2-Row Binary Matrix.

    Medium

    Given the following details of a matrix with n columns and 2 rows :

    • The matrix is a binary matrix, which means each element in the matrix can be 0 or 1.
    • The sum of elements of the 0-th(upper) row is given as upper.
    • The sum of elements of the 1-st(lower) row is given as lower.
    • The sum of elements in the i-th column(0-indexed) is colsum[i], where colsum is given as an integer array with length n.

    Your task is to reconstruct the matrix with upper, lower and colsum.

    Return it as a 2-D integer array.

    If there are more than one valid solution, any of them will be accepted.

    If no valid solution exists, return an empty 2-D array.

    Example 1:

    Input: upper = 2, lower = 1, colsum = [1,1,1]

    Output: [[1,1,0],[0,0,1]]

    Explanation: [[1,0,1],[0,1,0]], and [[0,1,1],[1,0,0]] are also correct answers.

    Example 2:

    Input: upper = 2, lower = 3, colsum = [2,2,1,1]

    Output: []

    Example 3:

    Input: upper = 5, lower = 5, colsum = [2,1,2,0,1,0,1,2,0,1]

    Output: [[1,1,1,0,1,0,0,1,0,0],[1,0,1,0,0,0,1,1,0,1]]

    Constraints:

    • 1 <= colsum.length <= 10^5
    • 0 <= upper, lower <= colsum.length
    • 0 <= colsum[i] <= 2
    • Constructor Detail

      • Solution

        public Solution()
    • Method Detail

      • reconstructMatrix

        public List<List<Integer>> reconstructMatrix​(int upper,
                                                     int lower,
                                                     int[] colsum)