#include <bits/stdc++.h>
using namespace std;
#define maxn 20
#define maxk 6000
#define INF 99999999
int n, m, S, Map[maxn][maxn];
int ans, CNST, val[maxn];
int f[maxn][maxn][maxk];
const int dx[4]={0, 0, -1, 1};
const int dy[4]={-1, 1, 0, 0};
bool vis[maxn][maxn][maxk];struct node
{int x, y, num;node(int xx = 0, int yy = 0, int zz = 0) { x = xx, y = yy, num = zz; }
}; queue <node> q;
node p[maxn];int read()
{int x = 0, k = 1;char c;c = getchar();while(c < '0' || c > '9') { if(c == '-') k = -1; c = getchar(); }while(c >= '0' && c <= '9') x = x * 10 + c - '0', c = getchar();return x * k;
}void spfa(int sx, int sy)
{for(int i = 1; i <= n; i ++)for(int j = 1; j <= m; j ++)for(int k = 0; k < CNST; k ++)f[i][j][k] = -INF;q.push(node(sx, sy, 0)), f[sx][sy][0] = 0, vis[sx][sy][0] = 1;while(!q.empty()){node now = q.front(); q.pop();vis[now.x][now.y][now.num] = 0;if(now.x == sx && now.y == sy)ans = max(ans, f[now.x][now.y][now.num]);for(int k = 0; k < 4; k ++){int xx = now.x + dx[k], yy = now.y + dy[k];if(xx <= 0 || xx > n || yy <= 0 || yy > m || Map[now.x][now.y]) continue;int num = now.num, Y = max(yy, now.y), del = 0;if(k <= 1){for(int i = 1; i <= S; i ++)if(p[i].y == Y && p[i].x < xx) {num ^= 1 << (i - 1);if((num >> i - 1) & 1) del += val[i];else del -= val[i];}}if(f[xx][yy][num] < f[now.x][now.y][now.num] + del - 1){f[xx][yy][num] = f[now.x][now.y][now.num] + del - 1;if(!vis[xx][yy][num]) vis[xx][yy][num] = 1, q.push(node(xx, yy, num));}}}
}int main()
{n = read(), m = read(), S = read();CNST = (1 << S) - 1;for(int i = 1; i <= S; i ++) val[i] = read();for(int i = 1; i <= n; i ++)for(int j = 1; j <= m; j ++){char c; cin >> c;if(c == '#') Map[i][j] = -1;else Map[i][j] = c - '0';if(Map[i][j] >= 1) p[Map[i][j]] = node(i, j);}for(int i = 1; i <= n; i ++)for(int j = 1; j <= m; j ++)if(!Map[i][j]) spfa(i, j);printf("%d\n", ans);return 0;
}