#include<iostream>

#include<cstdio>

#include<algorithm>

#include<cmath>

#include<cstring>

#include<string>

#include<stack>

#include<queue>

#include<deque>

#include<set>

#include<vector>

#include<map>

#include<functional>

#define fst first

#define sc second

#define pb push_back

#define mem(a,b) memset(a,b,sizeof(a))

#define lson l,mid,root<<1

#define rson mid+1,r,root<<1|1

#define lc root<<1

#define rc root<<1|1

#define lowbit(x) ((x)&(-x))

using namespace std;

typedef double db;

typedef long double ldb;

typedef long long ll;

typedef unsigned long long ull;

typedef pair<int,int> PI;

typedef pair<ll,ll> PLL;

const db eps = 1e-;

const int mod = 1e9+;

const int maxn = 1e6+;

const int maxm = 1e6+;

//const int inf = 0x3f3f3f3f;

const int inf = 1e9+;

const db pi = acos(-1.0);

vector<char>a[maxn];

vector<int>v[maxn],vis[maxn],wall[maxn],tp[maxn];

int n,m,d;

int dx[] = {,-,,};

int dy[] = {,,-,};

bool ck(int x, int y){

    if(x>=&&x<=n&&y>=&&y<=m)return true;

    return false;

}

queue<pair<PI, int>>seetq;

void seet(){

    while(!seetq.empty()){

        auto top = seetq.front();

        seetq.pop();

        int x = top.fst.fst;

        int y = top.fst.sc;

        int z = top.sc;

        //f(v[x][y])continue;

        //v[x][y]=1;

        if(z==d)continue;

        for(int i = ; i < ; i++){

            if(ck(x+dx[i],y+dy[i])&&v[x+dx[i]][y+dy[i]]==){

                seetq.push({{x+dx[i],y+dy[i]},z+});

                v[x+dx[i]][y+dy[i]]=;

            }

        }

    }

    return;

}

PI s,t;

char str[maxn];

int main() {

    scanf("%d %d %d", &n, &m, &d);

    for(int i = ; i <= n; i++){

        v[i].resize(m+);

        a[i].resize(m+);

        vis[i].resize(m+);

        wall[i].resize(m+);

        tp[i].resize(m+);

    }

    //getchar();

    for(int i = ; i <= n; i++){

        scanf("%s",str+);

        for(int j = ; j <= m; j++){

            v[i][j]=vis[i][j]=wall[i][j]=;

            tp[i][j]=inf;

            char c = str[j];

            a[i][j] = c;

            if(c=='S'){

                s = {i,j};

            }

            else if(c=='F'){

                t = {i,j};

            }

            else if(c=='M'){

                wall[i][j]=d+;

                seetq.push({{i,j},});

                v[i][j]=;

            }

        }

    }

    seet();

    queue<pair<PI,int>>q;

    q.push({{s.fst,s.sc},});

    int ans = -;

    if(v[s.fst][s.sc]==)return printf("-1"),;

    q.push({{s.fst,s.sc},});

    while(!q.empty()){

        auto top = q.front();

        q.pop();

        int x = top.fst.fst;

        int y = top.fst.sc;

        int z = top.sc;

        if(x==t.fst&&y==t.sc){

            ans=z;

            break;

        }

        if(vis[x][y])continue;

        vis[x][y]=;

        for(int i = ; i < ; i++){

            int nx = x+dx[i];

            int ny = y+dy[i];

            if(ck(nx,ny)&&vis[nx][ny]==&&v[nx][ny]!=){

                q.push({{nx,ny},z+});

            }

        }

    }

    printf("%d",ans);

    return ;

}

/*

4

2 2 3

2 3 4

1 4

0

 */