117: Minimum path sum

Given a 2D matrix with non-negative numbers, return minimum path sum from top left to bottom right corner

Note: You can move either down or right from any point

 

Example 1

Input:    0, 0, 0, 1, 1
          1, 1, 0, 1, 1
          1, 1, 0, 0, 0
          1, 1, 1, 1, 0

Output: 0

Example 2

Input:    1, 2, 1, 20, 0
          1, 6, 10, 1, 1
          1, 1, 1,  3, 1
          5, 5, 2,  1, 0

Output: 8