Gym - 101981K The 2018 ICPC Asia Nanjing Regional Contest K.Kangaroo Puzzle 暴力或随机

题面

题意:给你1个20*20的格子图,有的是障碍有的是怪,你可以每次指定上下左右的方向,然后所有怪都会向那个方向走,

如果2个怪撞上了,就融合在一起,让你给不超过5w步,让所有怪都融合

题解:我们可以选择一个边角的位置,每次都让一个怪移动到那里,同时暴力维护剩下的怪的位置,暴力走就可以了

不过后面发现好像直接随机也能过去？ 下面我们队3个人的...

 #include <iostream>
 #include<string>
 #include<cstring>
 #include<map>
 #include<queue>
 using namespace std;
 char puzzle[][];
 int kangaroo[][];
 bool tag[][];
 string ans;
 int n, m;
 const int a[][] = { {,},{-,},{,},{,-} };
 const string moving[] = { "D","U","R","L" };
 struct node {
     int x, y;
     string c;
 };
 node start;
 queue<node> fuck;
 string moveway[][];
 string addmove(int x)
 {
     if (x == )
         return moving[];
     if (x == )
         return moving[];
     if (x == )
         return moving[];
     return moving[];
 }
 bool check(int x, int y)
 {
     if (x >  && x <= n && y >  && y <= m && puzzle[x][y] != '')
         return true;
     else
         return false;
 }
 int guess_sum=;
 bool check_around(int x, int y)
 {
     int sum = ,j;
     for (int i = ; i < ; i++)
     {
         int ax = x + a[i][];
         int ay = y + a[i][];
         if (check(ax, ay) && kangaroo[ax][ay] == )
         {
             sum++;
             j = i;
         }
     }
     if (sum==)
     {
         guess_sum = j;
         return true;
     }
     else
         return false;
 }
 void BFS()
 {
     while (!fuck.empty())
     {
         node tmp = fuck.front();
         fuck.pop();
         for (int i = ; i < ; i++)
         {
             int x = tmp.x + a[i][];
             int y = tmp.y + a[i][];
             if (check(x, y) && kangaroo[x][y] ==  && tag[x][y] == false)
             {
                 node new_node;
                 new_node.x = x;
                 new_node.y = y;
                 new_node.c = addmove(i) + tmp.c;
                 moveway[x][y] = new_node.c;
                 tag[x][y] = true;
                 fuck.push(new_node);
             }
         }
     }
 }
 node needmove;
 bool judge()
 {
     needmove.c = "";
     for (int i = ; i <= n; i++)
         for (int j = ; j <= m; j++)
             if (i != start.x || j != start.y)
             {
                 if (kangaroo[i][j] > )
                 {
                     if (needmove.c == "" || needmove.c.size() < moveway[i][j].size())
                     {
                         needmove.x = i;
                         needmove.y = j;
                         needmove.c = moveway[i][j];
                     }
                 }
             }
     if (needmove.c != "")
         return false;
     return true;
 }
 void movex(int& x, int y, char c)
 {
     if (c == 'U'&&x -  >  && puzzle[x - ][y] != '')
         x--;
     if (c == 'D'&&x +  <= n && puzzle[x + ][y] != '')
         x++;
 }
 void movey(int x, int& y, char c)
 {
     if (c == 'L'&&y -  >  && puzzle[x][y - ] != '')
         y--;
     if (c == 'R'&&y +  <= m && puzzle[x][y + ] != '')
         y++;
 }
 void movekangaroo()
 {
     int tmp[][];
     for (int k = ; k < needmove.c.size(); k++)
     {
         for (int i = ; i <= n; i++)
             for (int j = ; j <= m; j++)
                 tmp[i][j] = kangaroo[i][j];
         char c = needmove.c[k];
         for (int i = ; i <= n; i++)
             for (int j = ; j <= m; j++)
                 if (kangaroo[i][j] > )
                 {
                     int newx = i, newy = j;
                     tmp[i][j] = ;
                     movex(newx, newy, c);
                     movey(newx, newy, c);
                     tmp[newx][newy] = ;
                 }
         for (int i = ; i <= n; i++)
             for (int j = ; j <= m; j++)
                 kangaroo[i][j] = tmp[i][j];
     }
 }
 int len = ;
 int main()
 {
     int i, j, k;
     ios::sync_with_stdio(false);
     cin.tie();
     cin >> n >> m;
     for (i = ; i <= n; i++)
         for (j = ; j <= m; j++)
             cin >> puzzle[i][j];
     memset(kangaroo, , sizeof(kangaroo));
     int sum = ;
     for (i = ; i <= n; i++)
         for (j = ; j <= m; j++)
             if (puzzle[i][j] == '')
             {
                 sum++;
                 kangaroo[i][j] = ;
             }
     if (sum ==  || sum == )
     {
         cout << "L\n";
         return ;
     }
     for (i = ; i <= n; i++)
         for (j = ; j <= m; j++)
             if (kangaroo[i][j] ==  && check_around(i, j))
             {
                 start.x = i;
                 start.y =j;
                 start.c = "";
             }
     for (i = ; i <= n; i++)
         for (j = ; j <= m; j++)
             moveway[i][j] = "";
     memset(tag, false, sizeof(tag));
     fuck.push(start);
     tag[start.x][start.y] = true;
     BFS();
     /*for (i = 1; i <= n; i++)
     {
         for (j = 1; j <= m; j++)
             if (kangaroo[i][j] > 0)
                 cout << i << " " << j << " " << moveway[i][j] << endl;
     }*/
     ans = "";
     while (!judge() && len < )      //get needmove
     {
         len += needmove.c.size();
         ans += needmove.c;
         movekangaroo();
     /*    cout << needmove.x << " " << needmove.y << " "<<needmove.c<<endl;
         for (i = 1; i <= n; i++)
         {
             for (j = 1; j <= m; j++)
                 cout << puzzle[i][j];
             for (j = 1; j <= 20; j++)
                 cout << " ";
             for (j = 1; j <= m; j++)
                 cout << kangaroo[i][j];
             cout << endl;
         }
         cout << endl;*/
     }
     if (len == )
         ans = ans + "R";
     cout << ans << "\n";
 }

 #include<bits/stdc++.h>
 #define ll long long
 #define PII pair<int,int>
 #define sl(x) scanf("%lld",&x)
 using namespace std;
 ll s[][];
 int main()
 {
      ll n,m,i,j,k;
      sl(n);sl(m);
      for(i = ;i < n;i++)
         scanf("%s",s[i]);
     srand(time());
     char ans[] = {'L','R','D','U'};
     int l = ,r = ;
     for(i = ;i <= ;i++)
     {
         char ch = ans[rand()%];
         printf("%c",ch);
     }
     puts("");
     return ;
 } 

 #include<bits/stdc++.h>

 using namespace std;

 #define mem(a,i) memset(a,i,sizeof(a))
 #define rep(i,a,b) for(int i=a;i<=b;++i)
 #define per(i,a,b) for(int i=a;i>=b;--i)
 const int maxn=;
 int n,m;
 char s[maxn][maxn];
 int a[maxn][maxn];
 int b[maxn][maxn];
 int p[]={,,,-};
 int q[]={,-,,};
 char ch[]={'L','R','U','D'};
 int deg(int x,int y) {
     int res=;
     rep(i,,) {
         int xx=x+p[i];
         int yy=y+q[i];
         if(xx<||xx>=n||yy<||yy>=m) continue;
         if(s[xx][yy]=='') continue;
         res++;
     }
     return res;
 }
 struct Node {
     int x,y;
     int step;
     Node() {}
     Node(int _x,int _y,int _step) {
         x=_x;
         y=_y;
         step=_step;
     }
 };
 bool vis[maxn][maxn];
 int f[maxn][maxn];
 queue<Node> Q;

 int main() {
     scanf("%d%d",&n,&m);
     rep(i,,n-) scanf("%s",s[i]);
     int ex,ey;
     int sum=;
     rep(i,,n-) {
         rep(j,,m-) {
             if(s[i][j]=='') a[i][j]=;
             else {
                 a[i][j]=;
                 sum++;
             }
         }
     }
     if(sum==) return *puts("");
     rep(i,,n-) {
         rep(j,,m-) {
             if(s[i][j]==''&&deg(i,j)==) {
                 ex=i;
                 ey=j;
             }
         }
     }
     // printf("%d %d\n",ex,ey);
     // puts("");
     int epoch=;
     int t=;
     while(t<=) {
         if(a[ex][ey]==sum) break;
         mem(vis,);
         mem(f,-);
         while(!Q.empty()) Q.pop();
         Node start(ex,ey,);
         Q.push(start);
         vis[ex][ey]=;
         int sx=ex,sy=ey,step=;
         while(!Q.empty()) {
             Node o=Q.front();
             Q.pop();
             if(step<o.step&&a[o.x][o.y]) {
                 step=o.step;
                 sx=o.x;
                 sy=o.y;
             }
             rep(i,,) {
                 int x=o.x+p[i];
                 int y=o.y+q[i];
                 if(x<||x>=n||y<||y>=m) continue;
                 if(s[x][y]==''||vis[x][y]) continue;
                 Node node(x,y,o.step+);
                 f[x][y]=i;
                 vis[x][y]=;
                 Q.push(node);
             }
         }
         // printf("%d %d\n",sx,sy);
         // rep(i,0,n-1) {
         //     rep(j,0,m-1) {
         //         printf("%d ",a[i][j]);
         //     }
         //     puts("");
         // }
         while() {
             if(sx==ex&&sy==ey) break;
             int o=f[sx][sy];
             printf("%c",ch[o]);
             // printf("%d %d\n",sx,sy);
             t++;
             mem(b,);
             rep(i,,n-) {
                 rep(j,,m-) {
                     if(s[i][j]=='') continue;
                     int x=i-p[o];
                     int y=j-q[o];
                     if(x<||x>=n||y<||y>=m||s[x][y]=='') {
                         b[i][j]+=a[i][j];
                     }
                     else {
                         b[x][y]+=a[i][j];
                     }
                 }
             }
             rep(i,,n-) {
                 rep(j,,m-) {
                     a[i][j]=b[i][j];
                 }
             }
             sx=sx-p[o];
             sy=sy-q[o];
         }
     }
     puts("");
     return ;
 }