Problem C. Minimum Path in Triangle

The tasks in this section contain test function calls. Please do not change this code; otherwise, the assignment may not be accepted.

Given a triangle array. The bird starts at the top, and for each step, it can move either left or right down (if it is on the index j at the current row, it can move to j or j+1 position on the next row). Return the minimum path cost among all possible paths from top to bottom.

Example 1

The orange path is minimum and costs 12.

Example 2

Input: triangle = [[1], [2, 1], [8, 3, 7], [5, 2, 6, 1]]

Output: 7

Explanation: The path looks like: