Compute minimum path sum in a triangle

Given a triangle of integers represented as a list of rows, find the **minimum path sum** from the top to the bottom. - From row `r` and index `c`, you may move to row `r+1` at index `c` **or** `c+1`. - Return the minimum possible sum along any valid path. ### Input - `triangle`: a list of lists of integers, where `triangle[i]` has length `i+1`. ### Output - An integer: the minimum path sum. ### Constraints (typical) - `1 <= number of rows <= 200` - Values can be negative or positive and fit in 32-bit signed integer. ### Example Triangle: - `[2]` - `[3, 4]` - `[6, 5, 7]` - `[4, 1, 8, 3]` Minimum path sum is `2 + 3 + 5 + 1 = 11`.