题解

#include<iostream>
#include<cmath>
#include<queue>
using namespace std;
int arr[205][205],dir[4][2]={{0,1},{1,0},{0,-1},{-1,0}},nx,ny,m,n,sum=0,ans=100,sx,sy,fx,fy;
char s;
bool flag=0,vis[205][205];
struct node{
	int x,y;
    int step;
};
int main(){
    cin>>m>>n;
    for(int i=1;i<=m;i++){
        for(int j=1;j<=n;j++){
            cin>>s;
            if(s=='S'){sx=i;sy=j;}
            else if(s=='T'){fx=i;fy=j;}
            else if(s=='.') arr[i][j]=0;
            else arr[i][j]=1;
        }
    }
    queue<node> q;
    q.push({sx,sy,0});
    vis[sx][sy]=1;
    while(!q.empty()){
        node t=q.front();
        q.pop();
        if(t.x==fx&&t.y==fy){
            flag=1;
            ans=t.step;
            break;
        }
        for(int i=0;i<=3;i++){
            int nx=t.x+dir[i][0];
            int ny=t.y+dir[i][1];
            if(nx<1||nx>m||ny<1||ny>n||arr[nx][ny]==1||vis[nx][ny]==1){
            	continue;    
            }
            q.push({nx,ny,t.step+1});
            vis[nx][ny]=1;
        }
    }
    if(flag==1) cout<<ans;
    else cout<<-1;
    return 0;
}