UVa 1377 / LA 3667 Ruler

之前WA是被这组数据卡掉了：

4

5 15 25 35

 

  1 #include <cstdio>

  2 #include <cstring>

  3 #include <cstdlib>

  4 #include <queue>

  5 #include <algorithm>

  6 

  7 using namespace std;

  8 

  9 struct node

 10 {

 11     int Haash;

 12     int use[8];

 13     int count;

 14 };

 15 

 16 

 17 bool vis[ (1 << 22) + 10 ];

 18 int d[54];

 19 int n, cnt;

 20 int idx[1000100];

 21 

 22 bool check( int a, int cur )

 23 {

 24     for ( int i = 0; i < cur; ++i )

 25         if ( d[i] == a ) return false;

 26     return true;

 27 }

 28 

 29 bool IfEnd( int a )

 30 {

 31     //printf( "all = %d\n", ( 1 << cnt ) - 1 );

 32     if ( a == (1 << cnt) - 1 ) return true;

 33     return false;

 34 }

 35 

 36 void chuli( node &cur, int add )

 37 {

 38     for ( int i = 0; i < cur.count; ++i )

 39     {

 40         int c = abs( add - cur.use[i] );

 41         if ( idx[c] != -1 ) cur.Haash |= ( 1 << idx[c] );

 42     }

 43 

 44     cur.use[ cur.count++ ] = add;

 45 

 46     sort( cur.use, cur.use + cur.count );

 47 

 48     return;

 49 }

 50 

 51 bool IfSame( int *num, int nn, int tar )

 52 {

 53     for ( int i = 0; i < nn; ++i )

 54         if ( num[i] == tar ) return true;

 55 

 56     return false;

 57 }

 58 

 59 node BFS()

 60 {

 61     memset( vis, false, sizeof(vis) );

 62     queue<node> Q;

 63 

 64     node st;

 65     st.Haash = 1;

 66     st.count = 1;

 67     st.use[0] = 0;

 68     vis[ st.Haash ] = true;

 69     Q.push( st );

 70 

 71     while ( !Q.empty() )

 72     {

 73         node cur = Q.front();

 74         Q.pop();

 75         //printf( "cnt=%d last=%d hash=%d\n", cur.count, cur.last, cur.Haash );

 76         if ( IfEnd( cur.Haash ) ) return cur;

 77 

 78         for ( int i = 0; i < cur.count; ++i )

 79         {

 80             for ( int j = 0; j < cnt; ++j )

 81             {

 82                 if ( cur.Haash & ( 1 << j ) ) continue;

 83 

 84                 int x = cur.use[i] + d[j];

 85                 if ( IfSame( cur.use, cur.count, x ) || x > d[ cnt - 1 ] ) continue;

 86 

 87                 node temp = cur;

 88                 chuli( temp, x );

 89 

 90                 if ( !vis[ temp.Haash ] )

 91                 {

 92                     vis[ temp.Haash ] = true;

 93                     if ( IfEnd( temp.Haash ) ) return temp;

 94 

 95                     Q.push(temp);

 96                 }

 97             }

 98 

 99             for ( int j = 0; j < cnt; ++j )

100             {

101                 if ( cur.Haash & ( 1 << j ) ) continue;

102 

103                 int x = cur.use[i] - d[j];

104                 if ( IfSame( cur.use, cur.count, x ) || x > d[ cnt - 1 ] || x < 0 ) continue;

105 

106                 node temp = cur;

107                 chuli( temp, x );

108 

109                 if ( !vis[ temp.Haash ] )

110                 {

111                     vis[ temp.Haash ] = true;

112                     if ( IfEnd( temp.Haash ) ) return temp;

113 

114                     Q.push(temp);

115                 }

116             }

117         }

118     }

119 

120     return st;

121 }

122 

123 int main()

124 {

125     int cas = 0;

126     while ( scanf( "%d", &n ), n )

127     {

128         d[0] = 0;

129         cnt = 1;

130         for ( int i = 0; i < n; ++i )

131         {

132             int a;

133             scanf( "%d", &a );

134             if ( check( a, cnt ) ) d[ cnt++ ] = a;

135         }

136         sort( d, d + cnt );

137 

138         memset( idx, -1, sizeof(idx) );

139         for ( int i = 0; i < cnt; ++i ) idx[ d[i] ] = i;

140 

141         node ans = BFS();

142 

143         printf( "Case %d:\n", ++cas );

144         printf( "%d\n", ans.count );

145         for ( int i = 0; i < ans.count; ++i )

146         {

147             if ( i ) putchar(' ');

148             printf( "%d", ans.use[i] );

149         }

150         puts("");

151     }

152     return 0;

153 }