HDU 3757 Evacuation Plan DP

跟 UVa 1474 - Evacuation Plan 一个题，但是在杭电上能交过，在UVa上交不过……不知道哪里有问题……

将施工队位置和避难所位置排序。

dp[i][j] 代表前 i 个避难所收留前 j 个施工队。

dp[i][j] = min( dp[i - 1][j - 1], dp[i][j - 1] ) + abs( b[i] - a[j] );

内存卡的比较死，要用滚动数组，并且记录路径的path[i][j]只能用bool型。MLE了四五次OTL……

 #include <cstdio>
 #include <cstring>
 #include <cstdlib>
 #include <algorithm>

 #define LL long long int

 using namespace std;

 const int MAXN = ;
 const LL INF = (LL) << ;

 struct Team
 {
     int id;
     LL pos;
 };

 LL dp[][MAXN];
 Team peo[MAXN];
 Team shlt[MAXN];
 int N, M;
 bool path[MAXN][MAXN];
 int ans[MAXN], getJ;

 bool cmp( Team a, Team b )
 {
     if ( a.pos != b.pos ) return a.pos < b.pos;
     return a.id < b.id;
 }

 LL DP()
 {
     int pre = , cur = ;

     for ( int i = ; i <= N; ++i )
     {
         if ( N - i >= M -  )
             dp[][i] = dp[][i - ] + abs( peo[i].pos - shlt[].pos );
         else dp[][i] = INF;
     }
     dp[][] = ;

     for ( int i = ; i <= M; ++i )
     {
         pre ^= ;
         cur ^= ;
         for ( int j = i; j <= N; ++j )
         {
             dp[cur][j] = dp[pre][j - ] + abs( peo[j].pos - shlt[i].pos );
             path[i][j] = true;

             if ( j > i && dp[cur][j - ] + abs( peo[j].pos - shlt[i].pos ) < dp[cur][j] )
             {
                 dp[cur][j] = dp[cur][j - ] + abs( peo[j].pos - shlt[i].pos );
                 path[i][j] = false;

             }

         }
     }
     return dp[cur][N];
 }

 void PrintPath( int i, int j )
 {
     if ( i ==  )
     {
         getJ = j;
         return;
     }

     switch ( path[i][j] )
     {
     case false:
         PrintPath( i, j -  );
         break;
     case true:
         PrintPath( i - , j -  );
         break;
     }

     ans[ peo[j].id ] = shlt[i].id;

     return;
 }

 int main()
 {
     while ( ~scanf( "%d", &N ) )
     {
         for ( int i = ; i <= N; ++i )
         {
             scanf( "%lld", &peo[i].pos );
             peo[i].id = i;
         }
         sort( peo + , peo + N + , cmp );

         scanf( "%d", &M );
         for ( int j = ; j <= M; ++j )
         {
             scanf( "%lld", &shlt[j].pos );
             shlt[j].id = j;
         }
         sort( shlt + , shlt + M + , cmp );

         printf( "%lld\n", DP() );
         PrintPath( M, N );
         while ( getJ >  )
         {
             ans[ peo[ getJ ].id ] = shlt[].id;
             --getJ;
         }

         for ( int i = ; i <= N; ++i )
         {
             if ( i !=  ) putchar(' ');
             printf( "%d", ans[i] );
         }
         puts("");
     }
     return ;
 }