1 //费用流初探
2 #include <iostream>
3 #include <queue>
4 #include <cstring>
5 #include <cstdio>
6 #include <algorithm>
7 using namespace std;
8 const int inf = 0x3f3f3f3f;
9 const int maxn = 110;
10 char gra[maxn][maxn];
11
12 const int maxv = 210;
13 const int maxe = 210 * 210;
14 struct Edge{
15 int u, v, cap, flow, cost;
16 int nxt;
17 Edge(int u = 0, int v = 0, int cap = 0, int flow = 0, int cost = 0, int nxt = 0) : u(u), v(v), cap(cap), flow(flow), cost(cost), nxt(nxt) {}
18 }e[maxe << 1];
19 int head[maxv];
20 int cnt = 0;
21 void init(){
22 memset(head, -1, sizeof(head));
23 cnt = 0;
24 }
25 void add(int u, int v, int cap, int flow, int cost){
26 e[cnt] = Edge(u, v, cap, flow, cost, head[u]);
27 head[u] = cnt++;
28 e[cnt] = Edge(v, u, 0, flow, -cost, head[v]);
29 head[v] = cnt++;
30 }
31 int mx[maxv], my[maxv], hx[maxv], hy[maxv];
32
33 int s, t, N;
34 int d[maxv], p[maxv], inq[maxv], a[maxv];
35 bool BellmandFord(int s, int t, int &flow, int &cost){
36 for(int i = 0; i < N; i++) d[i] = inf;
37 memset(inq, 0, sizeof inq);
38 d[s] = 0; inq[s] = 1; p[s] = 0; a[s] = inf;
39 queue<int> q;
40 q.push(s);
41 while(!q.empty()){
42 int u = q.front(); q.pop();
43 inq[u] = 0;
44 for(int i = head[u]; ~i; i = e[i].nxt){
45 Edge &tp = e[i];
46 if(tp.cap > tp.flow && d[tp.v] > d[u] + tp.cost){
47 d[tp.v] = d[u] + tp.cost;
48 p[tp.v] = i;
49 a[tp.v] = min(a[u], tp.cap - tp.flow);
50 if(!inq[tp.v]) {
51 q.push(tp.v);
52 inq[tp.v] = 1;
53 }
54 }
55 }
56 }
57 if(d[t] == inf) return false;
58 flow += a[t];
59 cost += d[t] * a[t];
60 int u = t;
61 while(u != s){
62 e[p[u]].flow += a[t];
63 e[p[u] ^ 1].flow -= a[t];
64 u = e[p[u]].u;
65 }
66 return true;
67 }
68 int MCMF(){
69 int flow = 0, cost = 0;
70 while(BellmandFord(s, t, flow, cost)) ;
71 return cost;
72 }
73
74 int main(){
75 //freopen("in.txt", "r", stdin);
76 //freopen("out.txt", "w", stdout);
77 int n, m;
78 while(scanf("%d %d", &n, &m) && (n || m)){
79 int cth = 0, ctm = 0;
80
81 init();
82 for(int i = 0; i < n; i++) {
83 scanf("%s", gra[i]);
84 for(int j = 0; j < m; j++){
85 if(gra[i][j] == 'H'){
86 hx[cth] = i;
87 hy[cth++] = j;
88 }
89 if(gra[i][j] == 'm'){
90 mx[ctm] = i;
91 my[ctm++] = j;
92 }
93 }
94 }
95 for(int i = 0; i < cth; i++){
96 for(int j = 0; j < ctm; j++){
97 int dis = abs(hx[i] - mx[j]) + abs(hy[i] - my[j]);
98 add(i, cth + j, 1, 0, dis);
99 }
100 }
101 s = cth + ctm;
102 t = s + 1;
103 N = t + 1;
104 for(int i = 0; i < cth; i++){
105 add(s, i, 1, 0, 0);
106 }
107 for(int i = 0; i < ctm; i++){
108 add(cth + i, t, 1, 0, 0);
109 }
110 int ans = MCMF();
111 printf("%d
", ans);
112 }
113 return 0;
114 }
