#include<iostream>
using namespace std;
const int N=101;
int n,m,r,a[N][N];
bool flag=false;
int dx[5]={0,1,-1,0,0},dy[5]={0,0,0,1,-1};
bool shit[N][N][N];
struct node
{
    int x,y,num,time;
}h[10000001];
void sb()
{
    int head=0,tail=1;
    h[1].x=1,h[1].y=1,h[1].num=0,h[1].time=0;
    shit[1][1][0]=1;
    while(head<tail)
    {
        head++;
        for(int i=1;i<=4;i++)
    {
        int xx,yy;
        for(int j=1;j<=n;j++)
        {
            xx=h[head].x+dx[i]*j,yy=h[head].y+dy[i]*j;
            if(xx<1||xx>n||yy<1||yy>m)
            {
                break;
            }
            if(a[xx][yy]==1)
            {
                continue;
            }
            tail++;
            h[tail].x=xx,h[tail].y=yy;
            h[tail].num=h[head].num,h[tail].time=h[head].time+1;
            if(j>1)
            {
                h[tail].num+=j;
            }
            if(h[tail].num>r)
            {
                tail--;
                break;
            }
            if(shit[xx][yy][h[tail].num]==1)
            {
                tail--;
                continue;
            }
            shit[xx][yy][h[tail].num]=1;
            if(xx==n&&yy==m)
            {
                cout<<h[tail].time;
                flag=true;
                return ;
            }
        }
    }
    }
}
int main()
{
    cin>>n>>m>>r;
    char c;
    for(int i=1;i<=n;i++)
    {
        for(int j=1;j<=m;j++)
        {
            cin>>c;
            if(c=='P')
            {
                a[i][j]=0;
            }
            else
            {
                a[i][j]=1;
            }
        }
    }
    sb();
    if(!flag)
    {
        cout<<"Impossible";
    }
    return 0;
}