531. Cheapest Way Across
Each cell of an m by n grid charges a toll. Starting at the top-left
cell and moving only right or down, print the smallest total toll paid on the way
to the bottom-right cell, counting both the first cell and the last.
This is the previous problem with two changes and no others. The two predecessors are combined with a minimum instead of a sum, because they are now alternatives to choose between rather than possibilities to total. And the cell's own toll is added, because a route's price is the sum of what it steps on.
The edges change meaning with it: the top row is no longer all ones but the running total along that row.
Constraints - `1 ≤ m ≤ 200` - `1 ≤ n ≤ 200` - `0 ≤ toll ≤ 1000`
Input
The first line contains two integers m and n.
Each of the next m lines contains n space-separated integers, the tolls of one row.
Output
Print one integer: the smallest total toll from the top-left cell to the bottom-right cell.
Hints
Four rungs, in order. The last two open once you have submitted an attempt. A wrong one counts.