C :

#include<stdio.h>
#include<string.h>
char a[202][202];
int b[202][202];
int n,m,sum;
void dfs(int x,int y,int t)
{
    if(a[x][y]=='a'&&t<sum)
        sum=t;
    if(!b[x][y]&&a[x][y]!='#'&&x-1>=0)
    {
        b[x][y]=1;
        if(a[x][y]=='x')
        dfs(x-1,y,t+2);
        else dfs(x-1,y,t+1);
        b[x][y]=0;

    }
    if(!b[x][y]&&a[x][y]!='#'&&x+1<n)
    {
        b[x][y]=1;
        if(a[x][y]=='x')
        dfs(x+1,y,t+2);
        else dfs(x+1,y,t+1);
        b[x][y]=0;

    }
    if(!b[x][y]&&a[x][y]!='#'&&y-1>=0)
    {
        b[x][y]=1;
        if(a[x][y]=='x')
        dfs(x,y-1,t+2);
        else dfs(x,y-1,t+1);
        b[x][y]=0;

    }
    if(!b[x][y]&&a[x][y]!='#'&&y+1<m)
    {
        b[x][y]=1;
        if(a[x][y]=='x')
        dfs(x,y+1,t+2);
        else dfs(x,y+1,t+1);
        b[x][y]=0;
    }
}
int main()
{
    int i,j,x1,x2,y1,y2;
    while(scanf("%d%d",&n,&m)!=EOF)
    {
        getchar();
        for(i=0;i<n;i++)
        {
            for(j=0;j<m;j++)
            {
                scanf("%c",&a[i][j]);
                if(a[i][j]=='r') x1=i,y1=j;
                if(a[i][j]=='a') x2=i,y2=j;
            }
            getchar();
        }
        memset(b,0,sizeof(b));
        sum=999999;
        dfs(x1,y1,0);
        if(sum==999999) printf("I'm so sorry, but I can fly! bye~\n");
        else printf("%d\n",sum);
    }
    return 0;
}

C++ :

#include<cstdio>
#include<iostream>
#include<cstring>
#include<algorithm>
#include<queue>

using namespace std;

int n, m;
char mp[205][205];
bool v[205][205];
int mv[4][2] =
{
    1, 0,
    0, 1,
    0, -1,
    -1, 0
};

struct Node
{
    int x;
    int y;
    int tep;
    Node(int tx, int ty, int tep)
    {
        x = tx;
        y = ty;
        this -> tep = tep;
    }
    Node(){}
};

int bfs(int sx, int sy)
{
    queue<Node> Q;
    Node node(sx, sy, 0);
    Node temp;
    Q.push(node);
    int x, y, tep;
    while(!Q.empty())
    {
        temp = Q.front();
        Q.pop();
        x = temp.x;
        y = temp.y;
        tep = temp.tep;
//        printf("x = %d y = %d tep = %d\n", x, y, tep);
        if(mp[x][y] == 'a')
        {
            return tep;
        }
        if(mp[x][y] == 'x')
        {
            mp[x][y] = '.';
            Node p(x, y, tep + 1);
            Q.push(p);
            continue;
        }
        for(int i = 0; i < 4; i++)
        {
            int tx = x + mv[i][0];
            int ty = y + mv[i][1];
            if(tx <0 || ty < 0 || tx >= n || ty >= m)
            {
                continue;
            }
            if(!v[tx][ty] && mp[tx][ty] != '#')
            {
                v[tx][ty] = true;
                Node p(tx, ty, tep + 1);
                Q.push(p);
            }
        }
    }
    return 0;
}

int main()
{
//    freopen("in.txt", "r", stdin);
//    freopen("out.txt", "w", stdout);
    while(cin >> n >> m)
    {
        int sx, sy;
        memset(v, false, sizeof(v));
        for(int i = 0; i < n; i++)
        {
            for(int k = 0; k < m; k++)
            {
                cin >> mp[i][k];
                if(mp[i][k] == 'r')
                {
                    sx= i;
                    sy = k;
                }
            }
        }
        int t = bfs(sx, sy);
        if(t)
        {
            printf("%d\n", t);
        }
        else
        {
            printf("I'm so sorry, but I can fly! bye~\n");
        }
    }
    return 0;
}