UVa532 Dungeon Master 三维迷宫
学习点:
scanf可以自动过滤空行
搜索时要先判断是否越界(L R C),再判断其他条件是否满足
bfs搜索时可以在入口处(push时)判断是否达到目标,也可以在出口处(pop时)
#include<cstdio> #include<cstring> #include<iostream> #include<string> #include<queue> using namespace std; const int N=31; const int dl[]={-1, 1, 0, 0, 0, 0}; const int dr[]={0, 0, -1, 1, 0, 0}; const int dc[]={0, 0, 0, 0, -1, 1}; struct State { State(int l, int r, int c, int d): l(l), r(r), c(c), d(d) {} int l, r, c; int d; }; int L, R, C; int SL, SR, SC; int EL, ER, EC; typedef char A[N][N][N]; A dungeon, vis; int bfs() { if(SL==EL && SR==EL && SC==EC) return 0; State s(SL, SR, SC, 0); vis[SL][SR][SC]=1; queue<State> q; q.push(s); while(!q.empty()) { State t=q.front(); q.pop(); //可以在出口判断 //if(t.l==EL && t.r==ER && t.c==EC) return t.d; for(int i=0;i<6;i++) { int nl=t.l+dl[i]; int nr=t.r+dr[i]; int nc=t.c+dc[i]; if(nl>=0 && nl<L && nr>=0 && nr<R && nc>=0 && nc<C && !vis[nl][nr][nc] && dungeon[nl][nr][nc]!='#') { //也可以在入口判断 if(nl==EL && nr==ER && nc==EC) return t.d+1; q.push(State(nl, nr, nc, t.d+1)); vis[nl][nr][nc]=1; } } } return -1; } int main() { #ifndef ONLINE_JUDGE freopen("./uva532.in", "r", stdin); #endif while(scanf("%d%d%d", &L, &R, &C)==3 && L && R && C) { for(int i=0;i<L;i++) { for(int j=0;j<R;j++) { scanf("%s", dungeon[i][j]); for(int k=0;k<C;k++) if(dungeon[i][j][k]=='S') SL=i, SR=j, SC=k; else if(dungeon[i][j][k]=='E') EL=i, ER=j, EC=k; } } memset(vis, 0, sizeof vis); int ans=bfs(); if(ans==-1) printf("Trapped!\n"); else printf("Escaped in %d minute(s).\n", ans); } return 0; }
// UVa532 Dungeon Master // Rujia Liu // 题意:三维迷宫中给定起点(字符S)和终点(字符E),墙是'#',空格是'.',求最短路长度 #include<cstdio> #include<cstring> #include<queue> using namespace std; struct State { int l, r, c; State(int l, int r, int c):l(l),r(r),c(c) {} }; const int maxn = 30 + 5; const int dl[] = {1,-1,0,0,0,0}; const int dr[] = {0,0,1,-1,0,0}; const int dc[] = {0,0,0,0,1,-1}; int L, R, C, d[maxn][maxn][maxn], vis[maxn][maxn][maxn]; char maze[maxn][maxn][maxn]; int bfs(int l1, int r1, int c1) { queue<State> Q; d[l1][r1][c1] = 0; vis[l1][r1][c1] = 1; Q.push(State(l1, r1, c1)); while(!Q.empty()) { State s = Q.front(); Q.pop(); for(int i = 0; i < 6; i++) { int newl = s.l + dl[i]; int newr = s.r + dr[i]; int newc = s.c + dc[i]; if(newl >= 0 && newl < L && newr >= 0 && newr < R && newc >= 0 && newc < C && maze[newl][newr][newc] != '#' && !vis[newl][newr][newc]) { Q.push(State(newl, newr, newc)); vis[newl][newr][newc] = 1; d[newl][newr][newc] = d[s.l][s.r][s.c] + 1; if(maze[newl][newr][newc] == 'E') return d[newl][newr][newc]; } } } return -1; } int main() { while(scanf("%d%d%d", &L, &R, &C) == 3 && L) { int l1, r1, c1; for(int i = 0; i < L; i++) for(int j = 0; j < R; j++) { scanf("%s", maze[i][j]); for(int k = 0; k < C; k++) if(maze[i][j][k] == 'S') { l1 = i; r1 = j; c1 = k; } } memset(vis, 0, sizeof(vis)); int ans = bfs(l1, r1, c1); if(ans >= 0) printf("Escaped in %d minute(s).\n", ans); else printf("Trapped!\n"); } return 0; }