捞

26分求条

#include<bits/stdc++.h>
using namespace std;
#define ll long long
const int N=1e6+5;

void in(int &x){
	char c=getchar();
	while (c<'0' || c>'9') c=getchar();
	for (x=0; c>='0' && c<='9'; c=getchar())
		x=x*10+c-'0';
}

char a[1005][1005];
int vis[1005][1005];
int dx[4] = {1, 0, -1, 0};
int dy[4] = {0, 1, 0, -1};
int n, m;
int rx, ry, ex, ey;
int xx, yy;
void goto_another(int nx,int ny) 
{
    for(int i=1;i<=n;i++)
    {
        for(int j=1;j<=m;j++)
        {
            if(a[i][j]==a[nx][ny]&&(i!=nx||j!=ny)) 
            {
                xx=i;
                yy=j;
                return ; 
            }
        }
    }
}
void dfs(int step, int x, int y)
{
	if(x == ex && y == ey)
	{
		cout << step << endl;
		exit(0);
	}
	if(a[x][y] >= 'A' && a[x][y] <= 'Z')
	{
		goto_another(x, y);
		x = xx;
		y = yy;
	}
	//cout << x << y << endl;
	for (int i = 0; i < 4; i++)
	{
		xx = x + dx[i];
		yy = y + dy[i];
		if(a[xx][yy] != '#' && !vis[xx][yy] && xx >= 1 && xx <= n && yy > 0 && yy <= m)
		{
			vis[xx][yy] = 1;
			dfs(step + 1, xx, yy);
		}
		
	}
}
int main(){
	in(n);in(m);
	for (int i = 1; i <= n; i++)
	{
		for (int j = 1; j <= m; j++)
		{
			cin >> a[i][j];
			if(a[i][j] == '=')
			{
				ex = i;
				ey = j;
			}
			else if(a[i][j] == '@')
			{
				rx = i;
				ry = j;
			}
		}
	}
	//vis[rx][ry] = 1;
	dfs(0, rx, ry);
	return 0;
}