[CF442A] Borya and Hanabi (暴力bitmask)

  1 #include <cstdio>
  2 #include <cstring>
  3 #include <algorithm>
  4 #include <vector>
  5 #include <map>
  6 #include <set>
  7 #include <bitset>
  8 #include <cmath>
  9 #include <numeric>
 10 #include <iterator>
 11 #include <iostream>
 12 #include <cstdlib>
 13 #include <functional>
 14 #include <queue>
 15 #include <stack>
 16 #include <string>
 17 #include <cctype>
 18 using namespace std;
 19 #define PB push_back
 20 #define MP make_pair
 21 #define SZ size()
 22 #define ST begin()
 23 #define ED end()
 24 #define CLR clear()
 25 #define ZERO(x) memset((x),0,sizeof(x))
 26 typedef long long LL;
 27 typedef unsigned long long ULL;
 28 typedef pair<int,int> PII;
 29 const double EPS = 1e-8;
 30 
 31 struct POINT{
 32     int x,y;
 33     int hash,idx;
 34 };
 35 
 36 int n,tot;
 37 vector<POINT> pts;
 38 set<int> se;
 39 vector<POINT> vx[10],vy[10];
 40 
 41 POINT GetPoint(const char* buf){
 42     POINT res;
 43     if( buf[0] == ‘R‘ ) res.x = 1;
 44     else if( buf[0] ==‘G‘ ) res.x = 2;
 45     else if( buf[0] == ‘B‘ ) res.x = 3;
 46     else if( buf[0] == ‘Y‘ ) res.x = 4;
 47     else if( buf[0] == ‘W‘ ) res.x = 5;
 48     res.y = buf[1] -‘0‘;
 49     res.hash = res.x*10+res.y;
 50     return res;
 51 }
 52 
 53 void SplitPoints() {
 54     for(int i=0;i<pts.size();i++){
 55         POINT &pt = pts[i];
 56         vx[pt.x].PB(pt);
 57         vy[pt.y].PB(pt);
 58         
 59 //        printf("vx[%d].PB(%d)\n",pt.x,pt.idx);
 60 //        printf("vy[%d].PB(%d)\n",pt.y,pt.idx);
 61     }
 62 }
 63 
 64 bool check(int mask,int out) {
 65     
 66     int vis[33];
 67     for(int i=0;i<33;i++) vis[i] = 0;
 68     
 69     for( int i=0;i<10;i++ ){
 70         if( (mask>>i)&1 ) {
 71             int now = i+1;
 72             if(now<=5) {
 73                 if( vx[now].size()==0 ) return false;
 74             } else {
 75                 now -= 5;
 76                 if( vy[now].size()==0 ) return false;
 77             }
 78         }
 79     }
 80     
 81 //    if(mask==261) puts("****");
 82     
 83     for( int i=0;i<10;i++ ) {
 84         if( (mask>>i)&1 ) {
 85             int now = i+1;
 86 //            if(mask==261) printf("now i=%d\n",now);
 87             if( now<=5 ) {
 88                 for(int j=0;j<vx[now].size();j++){
 89                     if( vis[vx[now][j].idx] == 2 ) continue;
 90                     vis[vx[now][j].idx]++;
 91                 }
 92             } else {
 93                 now -= 5;
 94                 for(int j=0;j<vy[now].size();j++){
 95                     if( vis[vy[now][j].idx]==2 ) continue;
 96                     vis[vy[now][j].idx]++;
 97                 }
 98             }
 99         }
100     }
101     
102     for(int i=0;i<10;i++){
103         if( (mask>>i)&1 ) {
104             int now = i+1;
105             if( now<=5 ) {
106                 // x
107                 int cnt = 0;
108                 for(int j=0;j<vx[now].size();j++) if(vis[vx[now][j].idx]<2) cnt++;
109                 if( cnt==1 ) {
110                     for(int j=0;j<vx[now].size();j++) if( vis[vx[now][j].idx] < 2)
111                     {
112                         vis[vx[now][j].idx] = 2; break;
113                     }
114                 }
115             } else {
116                 // y
117                 now -= 5;
118                 int cnt = 0;
119                 for(int j=0;j<vy[now].size();j++) if(vis[vy[now][j].idx]<2) cnt++;
120                 if( cnt==1 ) {
121                     for(int j=0;j<vy[now].size();j++) if(vis[vy[now][j].idx]<2){
122                         vis[vy[now][j].idx] = 2;
123                         break;
124                     }
125                 }
126             }
127         }
128     }
129     
130     bool res = true;
131     for(int i=0;i<tot;i++){
132 //        printf("vis[%d]=%d\n",i,vis[i]);
133         if(vis[i]<2&&i!=out) {
134             res = false;
135             break;
136         }
137     }
138     
139     return res;
140 }
141 
142 
143 
144 int main() {
145     tot = 0;
146     scanf("%d",&n);
147     for(int i=0;i<n;i++){
148         char buf[11];
149         scanf("%s",buf);
150         POINT pt = GetPoint(buf);
151         if( se.find(pt.hash) == se.end() ){
152             se.insert(pt.hash);
153             pt.idx = tot++;
154             pts.PB(pt);
155         }
156     }
157     
158 //    for(int i=0;i<pts.size();i++){
159 //        printf("%d,%d\n",pts[i].x,pts[i].y);
160 //    }
161 //    printf("size = %d\n",pts.size());
162     
163     SplitPoints();
164     int ans = 2*tot;
165     for(int i=0;i<(1<<10);i++) {
166         for(int j=0;j<tot;j++){
167             if( check(i,j) ) {
168                 //if(__builtin_popcount(i)==10&&fff==-1) printf("i=%d , ans = %d\n",i,__builtin_popcount(i));
169                 ans = min( ans,__builtin_popcount(i) );
170             }
171         }
172     }
173 //    printf("tot = %d\n", tot);
174     printf("%d\n",ans);
175     return 0;
176 }