MaxH's questions

我正在解决一些 leetcode 问题。但是对于这个难题，我不知道如何进一步加快我的算法速度。

https://leetcode.com/problems/minimum-obstacle-removal-to-reach-corner/submissions/1621824895

public class Solution {

    public int MinimumObstacles(int[][] grid) {
        int m = grid.Length;
        int n = grid[0].Length;
        var field = new MyDict(m, n, grid);
        field[(0,0)].wallsToHere = 0;
        List<Cell> toDo = [field[(0,0)]];
        while(!toDo.Contains(field[(m-1,n-1)])){
            var c = toDo.OrderBy(x=>x.wallsToHere).First();
            try{
                var testC = field[(c.m-1,c.n)];
                CheckCell(testC, c, toDo);
            }catch{}
            try{
                var testC = field[(c.m+1,c.n)];
                CheckCell(testC, c, toDo);
            }catch{}
            try{
                var testC = field[(c.m,c.n-1)];
                CheckCell(testC, c, toDo);
            }catch{}
            try{
                var testC = field[(c.m,c.n+1)];
                CheckCell(testC, c, toDo);
            }catch{}
            toDo.Remove(c);
            c.done = true;
        }
        return field[(m-1,n-1)].wallsToHere;
    }

    private void CheckCell(Cell testC, Cell c, List<Cell> toDo){
        if(!toDo.Contains(testC) && !testC.done){
            if (testC.wallsToHere > c.wallsToHere + testC.value){
                testC.wallsToHere = c.wallsToHere + testC.value;
            }
            toDo.Add(testC);
        }
    }
}

public class Cell(int value, int m, int n){
    public int value = value;
    public int wallsToHere = (int)Math.Pow(10,5)+1;
    public int m = m;
    public int n = n;
    public bool done = false;
}

public class MyDict:Dictionary<(int,int),Cell>
{
    public MyDict(int m, int n, int[][] grid){
        this.m=m;
        this.n=n;
        this._grid = grid;
    }

    private int m;
    private int n;
    private int[][] _grid;

    public new Cell this[(int,int) key]{
        get{
            if (base.Keys.Contains(key)){
                return base[key];
            }
            else if (key.Item1 < 0 || key.Item2 < 0 || key.Item1 > m || key.Item2 > n){
                throw new Exception();
            }
            else{
                Cell c = new Cell(_grid[key.Item1][key.Item2], key.Item1, key.Item2);
                base[key] = c;
                return c;
            }
        }
    }
}

除了我的 MyDict 实现之外，我不确定如何使用我的 Dijkstra 方法更快地解决这个问题。

如果可能的话，我怎样才能加快速度并改进，而不使用其他方法？