UVa 784 Maze Exploration

方法：dfs（flood fill）

dfs

code:

  1 #include <cstdio>
  2 #include <cstring>
  3 #include <algorithm>
  4 #include <iostream>
  5 #include <string>
  6 #include <vector>
  7 #include <stack>
  8 #include <bitset>
  9 #include <cstdlib>
 10 #include <cmath>
 11 #include <set>
 12 #include <list>
 13 #include <deque>
 14 #include <map>
 15 #include <queue>
 16 #include <fstream>
 17 #include <cassert>
 18 #include <unordered_map>
 19 #include <unordered_set>
 20 #include <cmath>
 21 #include <sstream>
 22 #include <time.h>
 23 #include <complex>
 24 #include <iomanip>
 25 #define Max(a,b) ((a)>(b)?(a):(b))
 26 #define Min(a,b) ((a)<(b)?(a):(b))
 27 #define FOR(a,b,c) for (ll (a)=(b);(a)<(c);++(a))
 28 #define FORN(a,b,c) for (ll (a)=(b);(a)<=(c);++(a))
 29 #define DFOR(a,b,c) for (ll (a)=(b);(a)>=(c);--(a))
 30 #define FORSQ(a,b,c) for (ll (a)=(b);(a)*(a)<=(c);++(a))
 31 #define FORC(a,b,c) for (char (a)=(b);(a)<=(c);++(a))
 32 #define FOREACH(a,b) for (auto &(a) : (b))
 33 #define rep(i,n) FOR(i,0,n)
 34 #define repn(i,n) FORN(i,1,n)
 35 #define drep(i,n) DFOR(i,n-1,0)
 36 #define drepn(i,n) DFOR(i,n,1)
 37 #define MAX(a,b) a = Max(a,b)
 38 #define MIN(a,b) a = Min(a,b)
 39 #define SQR(x) ((LL)(x) * (x))
 40 #define Reset(a,b) memset(a,b,sizeof(a))
 41 #define fi first
 42 #define se second
 43 #define mp make_pair
 44 #define pb push_back
 45 #define all(v) v.begin(),v.end()
 46 #define ALLA(arr,sz) arr,arr+sz
 47 #define SIZE(v) (int)v.size()
 48 #define SORT(v) sort(all(v))
 49 #define REVERSE(v) reverse(ALL(v))
 50 #define SORTA(arr,sz) sort(ALLA(arr,sz))
 51 #define REVERSEA(arr,sz) reverse(ALLA(arr,sz))
 52 #define PERMUTE next_permutation
 53 #define TC(t) while(t--)
 54 #define forever for(;;)
 55 #define PINF 1000000000000
 56 #define newline ‘\n‘
 57
 58 #define test if(1)if(0)cerr
 59 using namespace std;
 60 using namespace std;
 61 typedef vector<int> vi;
 62 typedef vector<vi> vvi;
 63 typedef pair<int,int> ii;
 64 typedef pair<double,double> dd;
 65 typedef pair<char,char> cc;
 66 typedef vector<ii> vii;
 67 typedef long long ll;
 68 typedef unsigned long long ull;
 69 typedef pair<ll, ll> l4;
 70 const double pi = acos(-1.0);
 71
 72 vector<string> v;
 73 int dx[] = {-1,0,1,0};
 74 int dy[] = {0,1,0,-1};
 75 void dfs(int x, int y)
 76 {
 77     v[x][y] = ‘#‘;
 78     for (int d = 0; d < 4; ++d)
 79     {
 80         int nx = x+dx[d], ny = y+dy[d];
 81
 82         if (nx < 0 || ny < 0 || nx >= v.size()-1 || ny >= v[nx].length() || v[nx][ny] != ‘ ‘)
 83         {continue;}
 84
 85         dfs(nx, ny);
 86     }
 87 }
 88 int main()
 89 {
 90     ios::sync_with_stdio(false);
 91     cin.tie(0);
 92     int T;  cin >> T;
 93     string line;
 94     getline(cin, line);
 95     for (int kase = 1; kase <= T; ++kase)
 96     {
 97         v.clear();
 98         while (getline(cin, line))
 99         {
100             v.push_back(line);
101             if (line[0] == ‘_‘) break;
102
103         }
104         bool done = false;
105         for (int i = 0; !done && i < v.size()-1; ++i) for (int j = 0; !done && j < v[i].length(); ++j)
106             if (v[i][j] == ‘*‘)
107             {
108                 dfs(i, j); done = true;
109             }
110         for (int i = 0; i < v.size(); ++i) cout << v[i] << newline;
111     }
112 }