Topcoder SRM655 DIV2 250 BichromeBoard 水

题意：给你一个网格图 ，每个网格中是W，B，两种颜色和 ？ 表示未知，相同颜色的网格不能相邻，问你能否满足条件

解题思路：W和B的位置 和 （i+j） 的奇偶有关。

解题代码：

  1 // BEGIN CUT HERE
  2 /*
  3
  4 */
  5 // END CUT HERE
  6 #line 7 "BichromeBoard.cpp"
  7 #include <cstdlib>
  8 #include <cctype>
  9 #include <cstring>
 10 #include <cstdio>
 11 #include <cmath>
 12 #include <algorithm>
 13 #include <vector>
 14 #include <string>
 15 #include <iostream>
 16 #include <sstream>
 17 #include <map>
 18 #include <set>
 19 #include <queue>
 20 #include <stack>
 21 #include <fstream>
 22 #include <numeric>
 23 #include <iomanip>
 24 #include <bitset>
 25 #include <list>
 26 #include <stdexcept>
 27 #include <functional>
 28 #include <utility>
 29 #include <ctime>
 30 using namespace std;
 31
 32 #define PB push_back
 33 #define MP make_pair
 34
 35 #define REP(i,n) for(i=0;i<(n);++i)
 36 #define FOR(i,l,h) for(i=(l);i<=(h);++i)
 37 #define FORD(i,h,l) for(i=(h);i>=(l);--i)
 38
 39 typedef vector<int> VI;
 40 typedef vector<string> VS;
 41 typedef vector<double> VD;
 42 typedef long long LL;
 43 typedef pair<int,int> PII;
 44
 45 int ok = 0 ;
 46
 47 class BichromeBoard
 48 {
 49         public:
 50         string ableToDraw(vector <string> str)
 51         {
 52             int n = str.size();
 53             int m = str[0].size();
 54             int st = 0 ;
 55             int ok = 1 ;
 56             for(int i = 0 ;i < n ; i ++)
 57                 for(int j = 0 ;j < m;j ++)
 58                 {
 59                     if(str[i][j] != ‘?‘){
 60                         if(str[i][j] == ‘B‘)
 61                         {
 62                            st = (i + j) % 2;
 63                            for(int i = 0;i < n;i ++)
 64                            {
 65                               for(int j = 0 ;j < m;j ++)
 66                               {
 67                                 if(str[i][j] == ‘W‘  && (i + j) % 2 == st)
 68                                     ok = 0 ;
 69                                 if(str[i][j] == ‘B‘  && (i + j) % 2 != st)
 70                                     ok = 0  ;
 71                               }
 72                            }
 73                         }else{
 74                            st = (i + j) % 2;
 75                            for(int i = 0;i < n;i ++)
 76                            {
 77                               for(int j = 0 ;j < m;j ++)
 78                               {
 79                                 if(str[i][j] == ‘B‘  && (i + j) % 2 == st)
 80                                     ok = 0 ;
 81                                 if(str[i][j] == ‘W‘  && (i + j) % 2 != st)
 82                                     ok = 0 ;
 83                               }
 84                            }
 85                         }
 86                         break;
 87                     }
 88                 }
 89             if(ok)
 90                 return "Possible";
 91             else return "Impossible";
 92         }
 93
 94 // BEGIN CUT HERE
 95     public:
 96     void run_test(int Case) { if ((Case == -1) || (Case == 0)) test_case_0(); if ((Case == -1) || (Case == 1)) test_case_1(); if ((Case == -1) || (Case == 2)) test_case_2(); if ((Case == -1) || (Case == 3)) test_case_3(); if ((Case == -1) || (Case == 4)) test_case_4(); if ((Case == -1) || (Case == 5)) test_case_5(); }
 97     private:
 98     template <typename T> string print_array(const vector<T> &V) { ostringstream os; os << "{ "; for (typename vector<T>::const_iterator iter = V.begin(); iter != V.end(); ++iter) os << ‘\"‘ << *iter << "\","; os << " }"; return os.str(); }
 99     void verify_case(int Case, const string &Expected, const string &Received) { cerr << "Test Case #" << Case << "..."; if (Expected == Received) cerr << "PASSED" << endl; else { cerr << "FAILED" << endl; cerr << "\tExpected: \"" << Expected << ‘\"‘ << endl; cerr << "\tReceived: \"" << Received << ‘\"‘ << endl; } }
100     void test_case_0() { string Arr0[] = {"W?W",
101  "??B",
102  "???"}; vector <string> Arg0(Arr0, Arr0 + (sizeof(Arr0) / sizeof(Arr0[0]))); string Arg1 = "Possible"; verify_case(0, Arg1, ableToDraw(Arg0)); }
103     void test_case_1() { string Arr0[] = {"W??W"}; vector <string> Arg0(Arr0, Arr0 + (sizeof(Arr0) / sizeof(Arr0[0]))); string Arg1 = "Impossible"; verify_case(1, Arg1, ableToDraw(Arg0)); }
104     void test_case_2() { string Arr0[] = {"??"}; vector <string> Arg0(Arr0, Arr0 + (sizeof(Arr0) / sizeof(Arr0[0]))); string Arg1 = "Possible"; verify_case(2, Arg1, ableToDraw(Arg0)); }
105     void test_case_3() { string Arr0[] = {"W???",
106  "??B?",
107  "W???",
108  "???W"}; vector <string> Arg0(Arr0, Arr0 + (sizeof(Arr0) / sizeof(Arr0[0]))); string Arg1 = "Possible"; verify_case(3, Arg1, ableToDraw(Arg0)); }
109     void test_case_4() { string Arr0[] = {"W???",
110  "??B?",
111  "W???",
112  "?B?W"}; vector <string> Arg0(Arr0, Arr0 + (sizeof(Arr0) / sizeof(Arr0[0]))); string Arg1 = "Impossible"; verify_case(4, Arg1, ableToDraw(Arg0)); }
113     void test_case_5() { string Arr0[] = {"B"}; vector <string> Arg0(Arr0, Arr0 + (sizeof(Arr0) / sizeof(Arr0[0]))); string Arg1 = "Possible"; verify_case(5, Arg1, ableToDraw(Arg0)); }
114
115 // END CUT HERE
116
117 };
118
119 // BEGIN CUT HERE
120 int main()
121 {
122         BichromeBoard ___test;
123         ___test.run_test(-1);
124         return 0;
125 }
126 // END CUT HERE