There is a pond with a rectangular shape. The pond is divided into a grid with H rows and W columns of squares. We will denote the square at the i-th row from the top and j-th column from the left by (i,\ j).

Some of the squares in the pond contains a lotus leaf floating on the water. On one of those leaves, S, there is a frog trying to get to another leaf T. The state of square (i,\ j) is given to you by a character a_{ij}, as follows:

* `.` : A square without a leaf.
* `o` : A square with a leaf floating on the water.
* `S` : A square with the leaf S.
* `T` : A square with the leaf T.



The frog will repeatedly perform the following action to get to the leaf T: "jump to a leaf that is in the same row or the same column as the leaf where the frog is currently located."

Snuke is trying to remove some of the leaves, other than S and T, so that the frog cannot get to the leaf T. Determine whether this objective is achievable. If it is achievable, find the minimum necessary number of leaves to remove.

Constraints

* 2 ≤ H, W ≤ 100
* a_{ij} is `.`, `o`, `S` or `T`.
* There is exactly one `S` among a_{ij}.
* There is exactly one `T` among a_{ij}.

Input

Input is given from Standard Input in the following format:


H W
a_{11} ... a_{1W}
:
a_{H1} ... a_{HW}


Output

If the objective is achievable, print the minimum necessary number of leaves to remove. Otherwise, print `-1` instead.

Examples

Input

3 3
S.o
.o.
o.T


Output

2


Input

3 4
S...
.oo.
...T


Output

0


Input

4 3
.S.
.o.
.o.
.T.


Output

-1


Input

10 10
.o...o..o.
....o.....
....oo.oo.
..oooo..o.
....oo....
..o..o....
o..o....So
o....T....
....o.....
........oo


Output

5
// package atcoder.arc.arc074;

import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.InputMismatchException;
import java.util.List;

public class Main {
    static final int INF = 1000000;

    public static void main(String[] args) {
        InputReader in = new InputReader(System.in);
        PrintWriter out = new PrintWriter(System.out);

        int h = in.nextInt();
        int w = in.nextInt();

        char[][] map = new char[h][];
        for (int i = 0; i < h ; i++) {
            map[i] = in.nextToken().toCharArray();
        }

        MaxFlowDinic dinic = new MaxFlowDinic();
        dinic.init(h+w+2);

        int source = h+w;
        int sink = source+1;
        for (int i = 0; i < h ; i++) {
            for (int j = 0; j < w ; j++) {
                if (map[i][j] == 'S') {
                    dinic.edge(source, i, INF);
                    dinic.edge(source, h+j, INF);
                } else if (map[i][j] == 'T') {
                    dinic.edge(i, sink, INF);
                    dinic.edge(h+j, sink, INF);
                } else if (map[i][j] == 'o') {
                    dinic.edge(i, h+j, 1);
                    dinic.edge(h+j, i, 1);
                }
            }
        }

        int ret = dinic.max_flow(source, sink);

        out.println(ret >= INF ? -1 : ret);
        out.flush();
    }

    public static class MaxFlowDinic {
        public List<int[]>[] graph;
        public int[] deg;

        public int[] level;
        public int[] itr;

        public int[] que;

        @SuppressWarnings("unchecked")
        public void init(int size) {
            graph = new List[size];
            for (int i = 0; i < size ; i++) {
                graph[i] = new ArrayList<int[]>();
            }
            deg = new int[size];
            level = new int[size];
            itr = new int[size];
            que = new int[size+10];
        }
        public void edge(int from, int to, int cap) {
            int fdeg = deg[from];
            int tdeg = deg[to];
            graph[from].add(new int[]{to, cap, tdeg});
            graph[to].add(new int[]{from, 0, fdeg});
            deg[from]++;
            deg[to]++;
        }

        public int dfs(int v, int t, int f) {
            if (v == t) return f;
            for (int i = itr[v] ; i < graph[v].size() ; i++) {
                itr[v] = i;
                int[] e = graph[v].get(i);
                if (e[1] > 0 && level[v] < level[e[0]]) {
                    int d = dfs(e[0], t, Math.min(f, e[1]));
                    if (d > 0) {
                        e[1] -= d;
                        graph[e[0]].get(e[2])[1] += d;
                        return d;
                    }
                }
            }
            return 0;
        }

        public void bfs(int s) {
            Arrays.fill(level, -1);
            int qh = 0;
            int qt = 0;
            level[s] = 0;
            que[qh++] = s;
            while (qt < qh) {
                int v = que[qt++];
                for (int i = 0; i < graph[v].size() ; i++) {
                    int[] e = graph[v].get(i);
                    if (e[1] > 0 && level[e[0]] < 0) {
                        level[e[0]] = level[v] + 1;
                        que[qh++] = e[0];
                    }
                }
            }
        }

        public int max_flow(int s, int t) {
            int flow = 0;
            while (true) {
                bfs(s);
                if (level[t] < 0) {
                    return flow;
                }
                Arrays.fill(itr, 0);
                while (true) {
                    int f = dfs(s, t, Integer.MAX_VALUE);
                    if (f <= 0) {
                        break;
                    }
                    flow += f;
                }
            }
        }
    }

    static class InputReader {
        private InputStream stream;
        private byte[] buf = new byte[1024];
        private int curChar;
        private int numChars;

        public InputReader(InputStream stream) {
            this.stream = stream;
        }

        private int[] nextInts(int n) {
            int[] ret = new int[n];
            for (int i = 0; i < n; i++) {
                ret[i] = nextInt();
            }
            return ret;
        }

        private int[][] nextIntTable(int n, int m) {
            int[][] ret = new int[n][m];
            for (int i = 0; i < n; i++) {
                for (int j = 0; j < m; j++) {
                    ret[i][j] = nextInt();
                }
            }
            return ret;
        }

        private long[] nextLongs(int n) {
            long[] ret = new long[n];
            for (int i = 0; i < n; i++) {
                ret[i] = nextLong();
            }
            return ret;
        }

        private long[][] nextLongTable(int n, int m) {
            long[][] ret = new long[n][m];
            for (int i = 0; i < n; i++) {
                for (int j = 0; j < m; j++) {
                    ret[i][j] = nextLong();
                }
            }
            return ret;
        }

        private double[] nextDoubles(int n) {
            double[] ret = new double[n];
            for (int i = 0; i < n; i++) {
                ret[i] = nextDouble();
            }
            return ret;
        }

        private int next() {
            if (numChars == -1)
                throw new InputMismatchException();
            if (curChar >= numChars) {
                curChar = 0;
                try {
                    numChars = stream.read(buf);
                } catch (IOException e) {
                    throw new InputMismatchException();
                }
                if (numChars <= 0)
                    return -1;
            }
            return buf[curChar++];
        }

        public char nextChar() {
            int c = next();
            while (isSpaceChar(c))
                c = next();
            if ('a' <= c && c <= 'z') {
                return (char) c;
            }
            if ('A' <= c && c <= 'Z') {
                return (char) c;
            }
            throw new InputMismatchException();
        }

        public String nextToken() {
            int c = next();
            while (isSpaceChar(c))
                c = next();
            StringBuilder res = new StringBuilder();
            do {
                res.append((char) c);
                c = next();
            } while (!isSpaceChar(c));
            return res.toString();
        }

        public int nextInt() {
            int c = next();
            while (isSpaceChar(c))
                c = next();
            int sgn = 1;
            if (c == '-') {
                sgn = -1;
                c = next();
            }
            int res = 0;
            do {
                if (c < '0' || c > '9')
                    throw new InputMismatchException();
                res *= 10;
                res += c-'0';
                c = next();
            } while (!isSpaceChar(c));
            return res*sgn;
        }

        public long nextLong() {
            int c = next();
            while (isSpaceChar(c))
                c = next();
            long sgn = 1;
            if (c == '-') {
                sgn = -1;
                c = next();
            }
            long res = 0;
            do {
                if (c < '0' || c > '9')
                    throw new InputMismatchException();
                res *= 10;
                res += c-'0';
                c = next();
            } while (!isSpaceChar(c));
            return res*sgn;
        }

        public double nextDouble() {
            return Double.valueOf(nextToken());
        }

        public boolean isSpaceChar(int c) {
            return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
        }

        public interface SpaceCharFilter {
            public boolean isSpaceChar(int ch);
        }
    }

    static void debug(Object... o) {
        System.err.println(Arrays.deepToString(o));
    }
}
