uva 1601

#include<cstdio>
#include<cstring>
#include<algorithm>
#include<cstdlib>
#include<iostream>
#include<queue>
#include<vector>
#include<sstream>
#include<cmath>
#include<queue>
#include<cctype>
using namespace std;

const int  maxn = 16+2, maxc = 18*18;
int w, h, n;
char buf[maxn][maxn];
int deg[maxc], G[maxc][5];
const int dx[] = {0,1,0,-1,0};
const int dy[] = {0,0,1,0,-1};
int s[3],t[3];
int d[maxc][maxc][maxc];

int ID(int a, int b, int c) {
  return (a<<16)|(b<<8)|c;
}

bool conflict(int aa,int bb,int a,int b){
    if((aa == bb)||(aa == b && bb == a)) return true;
    return false;
}

int solve(){
   memset(d, -1, sizeof(d));
   queue<int>q;
   d[s[0]][s[1]][s[2]] = 0;
   q.push(ID(s[0],s[1],s[2]));
   while(!q.empty()){
      int u = q.front(); q.pop();
      int a = (u>>16)&0xff, b = (u>>8)&0xff, c = u&0xff;
      for(int i = 0; i < deg[a]; i++){
          int a2 = G[a][i];
          for(int j = 0; j < deg[b]; j++){
                int b2 = G[b][j];
                if(conflict(a2,b2,a,b)) continue;
                for(int k = 0; k < deg[c]; k++){
                    int c2 = G[c][k];
                    if(d[a2][b2][c2]!=-1) continue;
                    if(conflict(a2,c2,a,c)) continue;
                    if(conflict(b2,c2,b,c)) continue;
                    d[a2][b2][c2] = d[a][b][c] +1;
                    if(a2 == t[0] && b2 == t[1] && c2 == t[2]) return d[a2][b2][c2];

                    q.push(ID(a2,b2,c2));
                }
          }
       }
   }
   return -1;
}

int main(){
   while(scanf("%d%d%d\n",&w,&h,&n) == 3 && w){
      for(int i = 0; i < h; i++)
         fgets(buf[i],maxn,stdin);

      memset(s,-1,sizeof(s));
      memset(t,-1,sizeof(t));
      int cur = 0;
      int x[maxc], y[maxc], id[maxn][maxn];
      memset(id,-1,sizeof(id));
      for(int i =0; i < h; i++)
         for(int j = 0; j < w; j++){
            if(buf[i][j]!='#'){
                id[i][j] = cur;
                x[cur] = i; y[cur] = j;
                if(islower(buf[i][j])) s[buf[i][j]-'a'] = cur;
                else if(isupper(buf[i][j])) t[buf[i][j]-'A'] = cur;
                cur++;
            }
         }

      for(int k = 0; k < cur; k++){
          deg[k] = 0;
          for(int i = 0; i < 5; i++){
              int xx = x[k] + dx[i];
              int yy = y[k] + dy[i];
              if(buf[xx][yy]!='#'){
                  G[k][deg[k]++] = id[xx][yy];
              }
          }
      }

      if(n <= 2){deg[cur] = 1;s[2] = t[2] = cur;G[cur][0] = cur;cur++;}
      if(n <= 1){deg[cur] = 1;s[1] = t[1] = cur;G[cur][0] = cur;}

      printf("%d\n",solve());
   }
   return 0;
}

不服？还不够暴力？？ 求指点

#include<cstdio>
#include<cstring>
#include<algorithm>
#include<cstdlib>
#include<iostream>
#include<queue>
#include<vector>
#include<sstream>
#include<cmath>
#include<queue>
#include<cctype>
using namespace std;
const int maxn = 16+2, maxc = 16*16*16*16*16*16;
int w, h, n, GOAL;
char buf[maxn][maxn];
bool visit[maxc];
const int dx[] = {0,1,0,-1,0};
const int dy[] = {0,0,1,0,-1};

struct node{
   int x,y;
};

struct Node{
    node pos[3];
    int temp;
    bool operator < (const Node &rhy) const{
       return temp > rhy.temp;
    }
}first,goal;

bool inside(Node t){
   for(int i = 0;i < n; i++){
      int x = t.pos[i].x, y = t.pos[i].y;
      if(!(x>=0&&y>=0&&x<h&&y<w&&buf[x][y] != '#')) return false;
   }
   return true;
}


int f(Node t){
  if(n == 3)
         return t.pos[0].x*16*16*16*16*16+t.pos[0].y*16*16*16*16+
         t.pos[1].x*16*16*16+t.pos[1].y*16*16+
         t.pos[2].x*16+t.pos[2].y;
  else if(n == 2){
         return t.pos[0].x*16*16*16+t.pos[0].y*16*16+
         t.pos[1].x*16+t.pos[1].y;
  }
  else {
        return t.pos[0].x*16+t.pos[0].y;
  }
}

void read_input(){
   first.temp = 0;
   for(int i = 0; i < h; i++){
      for(int j = 0; j < w; j++){
         scanf("%c",&buf[i][j]);
         if(islower(buf[i][j])) first.pos[buf[i][j] - 'a'] = {i,j};
         else if(isupper(buf[i][j])) goal.pos[buf[i][j] - 'A'] = {i,j};
      }
      getchar();
   }
   GOAL = f(goal);
}

bool g(Node t,Node s){
   for(int i = 0;i < n;i++)
      for(int j = i+1;j < n ;j++){
          if(memcmp(&t.pos[i],&t.pos[j],sizeof(node)) == 0) return false;
      }
   for(int i = 0;i < n;i++)
      for(int j = i+1;j < n ;j++){
          if(memcmp(&t.pos[i],&s.pos[j],sizeof(node)) == 0 && memcmp(&t.pos[j],&s.pos[i],sizeof(node)) == 0) return false;
      }
   return true;
}

void solve(){
   memset(visit,false,sizeof(visit));
   priority_queue<Node>pq;
   pq.push(first);
   visit[f(first)] = true;
   while(!pq.empty()){
      Node s = pq.top();
      pq.pop();
      for(int i = 0; i < 5; i++)
         for(int j = 0; j < 5; j++)
            for(int k = 0; k < 5; k++){
                Node t;
                memcpy(&t,&s,sizeof(s));
                t.pos[0].x += dx[i];
                t.pos[0].y += dy[i];
                t.pos[1].x += dx[j];
                t.pos[1].y += dy[j];
                t.pos[2].x += dx[k];
                t.pos[2].y += dy[k];
                if(inside(t)&&visit[f(t)] == false&&g(t,s)){
                    t.temp++;
                    if(f(t) == GOAL){
                         printf("%d\n",t.temp);
                         return;
                    }
                    pq.push(t);
                    visit[f(t)] = true;
                }
            }
   }
}

int main(){
   while(scanf("%d%d%d\n",&w,&h,&n) == 3 && w && h && n){
      read_input();
      solve();
   }
   return 0;
}