Package g1001_1100.s1074_number_of_submatrices_that_sum_to_target

Class Solution

  • All Implemented Interfaces:
    
public final class Solution

    1074 - Number of Submatrices That Sum to Target.

    Hard

    Given a matrix and a target, return the number of non-empty submatrices that sum to target.

    A submatrix x1, y1, x2, y2 is the set of all cells matrix[x][y] with x1 <= x <= x2 and y1 <= y <= y2.

    Two submatrices (x1, y1, x2, y2) and (x1', y1', x2', y2') are different if they have some coordinate that is different: for example, if x1 != x1'.

    Example 1:

    Input: matrix = \[\[0,1,0],1,1,1,0,1,0], target = 0

    Output: 4

    Explanation: The four 1x1 submatrices that only contain 0.

    Example 2:

    Input: matrix = \[\[1,-1],-1,1], target = 0

    Output: 5

    Explanation: The two 1x2 submatrices, plus the two 2x1 submatrices, plus the 2x2 submatrix.

    Example 3:

    Input: matrix = \[\[904]], target = 0

    Output: 0

    Constraints:

    • 1 <= matrix.length <= 100

    • 1 <= matrix[0].length <= 100

    • -1000 <= matrix[i] <= 1000

    • -10^8 <= target <= 10^8

    • Nested Class Summary

      Nested Classes 
      Modifier and Type Class Description

    • Field Summary

      Fields 
      Modifier and Type Field Description

    • Constructor Summary

      Constructors 
      Constructor Description
      Solution()

    • Enum Constant Summary

      Enum Constants 
      Enum Constant Description

    • Method Summary

      Modifier and Type Method Description
      final Integer numSubmatrixSumTarget(Array<IntArray> matrix, Integer target)

      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait