Melt (Unpivot)
MediumData EngineeringSortingMatrixSQL
Description
Given a 2D table, unpivot it from wide to long format: return one [rowIndex, columnIndex, value] triple per cell, in row-major order.
Examples
Input:
[[5,6],[7,8]]Output:
[[0,0,5],[0,1,6],[1,0,7],[1,1,8]]Explanation:
Every cell of the table becomes its own row labelled with its row and column position alongside the value.
Input:
[[1]]Output:
[[0,0,1]]Explanation:
Every cell of the table becomes its own row labelled with its row and column position alongside the value.
Input:
[[1,2,3]]Output:
[[0,0,1],[0,1,2],[0,2,3]]Explanation:
Every cell of the table becomes its own row labelled with its row and column position alongside the value.
Constraints
- •
1 ≤ rows, cols ≤ 10³