没必要用Map的直接用数组就行了，从A到Z最多26对，直接数组实现
```java
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.LinkedList;
import java.util.Queue;
public class Main {
static BufferedReader bf = new BufferedReader(new InputStreamReader(System.in));
static int X[] = new int[]{0,0,1,-1};
static int Y[] = new int[]{1,-1,0,0};
static int n,m;
static char map[][];
static boolean check[][];
static int csm[][] = new int[26][4];
static int sx,sy,tx,ty;
public static void main(String[] args) throws IOException {
String s[] = bf.readLine().split(" ");
n = Integer.parseInt(s[0]);
m = Integer.parseInt(s[1]);
map = new char[n+1][m+1];
check = new boolean[n+1][m+1];
for (int i = 1; i <= n; i++) {
String str = bf.readLine();
for (int j = 1; j <= m; j++) {
map[i][j] = str.charAt(j-1);
if(map[i][j]>='A'&&map[i][j]<='Z'){
int loc = map[i][j] - 'A';
if(csm[loc][0]==0){
csm[loc][0] = i;
csm[loc][1] = j;
}
else {
csm[loc][2] = i;
csm[loc][3] = j;
}
}
if(map[i][j]=='@'){
sx = i;
sy = j;
}
if(map[i][j]=='='){
tx = i;
ty = j;
}
}
}
System.out.println(bfs());
}
static int bfs(){
Queue<int[]> q = new LinkedList<>();
q.offer(new int[]{sx,sy});
int time = 0;
check[sx][sy] = true;
while (!q.isEmpty()){
int size = q.size();
while(size-->0){
int arr[] = q.poll();
int x = arr[0];
int y = arr[1];
if(x==tx&&y==ty){
return time;
}
if(map[x][y]>='A'&&map[x][y]<='Z'){
int loc = map[x][y] - 'A';
check[x][y] = true;
if(x==csm[loc][0]&&y==csm[loc][1]){
x = csm[loc][2];
y = csm[loc][3];
}
else {
x = csm[loc][0];
y = csm[loc][1];
}
}
for (int i = 0; i < 4; i++) {
int nx = x+X[i];
int ny = y+Y[i];
if(test(nx,ny)){
q.offer(new int[]{nx,ny});
check[nx][ny] = true;
}
}
}
time++;
}
return 0;
}
static boolean test(int x,int y){
if(x<1||x>n||y<1||y>m)return false;
if(map[x][y]=='#')return false;
if(check[x][y])return false;
return true;
}
}
```
by _Yan @ 2023-05-29 11:02:24