// Slower C++ solution:
/*

*

*/

#include<iostream>

#include<cstring>

#include<cstdio>

#include<cmath>

#include<string>

#include<queue>

#define CLR(ARR,NUM) memset(ARR,NUM,sizeof(ARR))

#define GETNUM(NUM) scanf("%d",&NUM)

#define faster_io() ios_base::sync_with_stdio(false)

using namespace std;

const int MAXN = 1010;

char map[MAXN][MAXN];

bool vis[10][MAXN][MAXN];

struct node{

	int x;

	int y;

	int deep;

	int n;

};

int dx[]={0,0,1,-1};

int dy[]={1,-1,0,0};



int main()

{

	CLR(vis,false);

	CLR(map,'X');

	int h,w,n;

	cin >> h >> w >> n;

	getchar();

	int sx,sy;

	for(int i=1;i<=h;i++){

		for(int j=1;j<=w;j++){

			map[i][j]=getchar();

			if(map[i][j]=='S'){

				sx=i;

				sy=j;

			}

		}

		getchar();

	}

	node t;

	t.x=sx;

	t.y=sy;

	t.deep=0;

	t.n=0;

	queue<node>q;

	vis[0][sx][sy]=true;

	q.push(t);

	int ans = -1;

	while(!q.empty()){

		node cur=q.front();

		if(cur.n==n){

			ans=cur.deep;

			break;

		}

		q.pop();

		for(int i=0;i<4;i++){

			int tx=cur.x+dx[i];

			int ty=cur.y+dy[i];

			if(map[tx][ty]!='X'&&!vis[cur.n][tx][ty]){

				node t = cur;

				t.x=tx;

				t.y=ty;

				t.deep++;

				if(map[tx][ty]=='1'+t.n){

					t.n++;

				}

				vis[t.n][tx][ty]=true;

				q.push(t);

			}

		}

	}

	cout << ans << endl;

	return 0;

}

// Faster C++ solution for the same problem (measured speedup: 2.5043578337817602x):


#include<iostream>

#include<queue>

#include<string.h>

using namespace std;

char map[1005][1005];

char map1[1005][1005];

int a[1005][1005];

int m,n,q,num=0;

int main()

{

	int x,y;

	cin>>m>>n>>q;

	for(int i=0;i<m;i++)

	{

		for(int j=0;j<n;j++)

		{

			cin>>map[i][j];

			if(map[i][j]=='S')

				{

					x=i;

					y=j;

				 map[x][y]='0';

				}

		}

	}

	for(int i=0;i<m;i++)

		{

			for(int j=0;j<n;j++)

			{

				map1[i][j]=map[i][j];



			}

		}



	for(int k=1;k<=q;k++)

	{

			queue<int> ac;

			queue<int> ak;



		for(int i=0;i<m;i++)

		{

			for(int j=0;j<n;j++)

			{

				map[i][j]=map1[i][j];

				if(map1[i][j]-'0'==k-1)

				{

					x=i;

					y=j;

					map[x][y]='X';

				}

			}

		}

		memset(a,0,sizeof(a));

		ac.push(x);

		ak.push(y);

		while(!ac.empty())

		{

			x=ac.front();

			y=ak.front();

			ac.pop();

			ak.pop();

			if(x+1<m)

			{

				if(map[x+1][y]!='X')

				{

					if(map[x+1][y]-'0'==k)

					{

						num+=a[x][y];

						num+=1;

						break;

					}

						map[x+1][y]='X';

						ac.push(x+1);

						ak.push(y);

						a[x+1][y]=a[x][y]+1;

				}

			}

				if(x-1>=0)

				{

					if(map[x-1][y]!='X')

					{



						if(map[x-1][y]-'0'==k)

						{

							num+=a[x][y]+1;

							break;

						}

						map[x-1][y]='X';

						ac.push(x-1);

						ak.push(y);

						a[x-1][y]=a[x][y]+1;

					}

				}

			if(y+1<n)

			{

				if(map[x][y+1]!='X')

				{



					if(map[x][y+1]-'0'==k)

					{

						num+=a[x][y]+1;

						break;

					}



						map[x][y+1]='X';

						ac.push(x);

						ak.push(y+1);

						a[x][y+1]=a[x][y]+1;

				}

			}

			if(y-1>=0)

			{

				if(map[x][y-1]!='X')

				{



					if(map[x][y-1]-'0'==k)

					{

						num+=a[x][y]+1;

						break;

					}



						map[x][y-1]='X';

						ac.push(x);

						ak.push(y-1);

						a[x][y-1]=a[x][y]+1;

				}

			}

		}

	}

	cout<<num<<endl;

	return 0;

}