Rokua P1433 eating cheese Label:dfs && pruning ex

Title Description

There are n pieces of cheese in the room. A little mouse to eat them all, ask at least how many distance to run? The mouse begins at (0,0) point.

Input/output format

Input format:

First row one number n (n<=15)

The next 2 real numbers for each line represent the coordinates of the block I cheese.

Distance between two points formula =sqrt ((X1-X2) * (X1-X2) + (y1-y2) * (Y1-Y2))

Output format:

A number that represents the minimum distance to run and retains 2 decimal places.

Input and Output Sample input example # #:

41 11-1-1 1-1-1

Sample # # of output:

7.41

Code

1#include <iostream>2#include <cstring>3#include <cstdio>4#include <vector>5#include <cmath>6#include <map>7#include <algorithm>8 #defineINF 0x3f3f3f3f9 using namespacestd;Ten  Onemap<int,Double>m; Avector<int> g[ -]; -vector<Double> c[ -]; - intn,vis[ -]; the Doubleans=INF; -  - structcc{ -     Doublex, y; +}nod[ -]; -  + DoubleDisintAintb) { A     returnsqrt ((nod[a].x-nod[b].x) * (nod[a].x-nod[b].x) + (NOD[A].Y-NOD[B].Y) * (nod[a].y-nod[b].y)); at } -  - intLook_up_table (DoubleLen) { -     Long LongH=0; -      for(intI=1; i<=n;i++){ -         if(Vis[i]) h=h*Ten+i; in     } -     if(M.count (H)) { to         if(Len>m[h])return 0; +m[h]=Len; -         return 1; the     } *     Else{ $m[h]=Len;Panax Notoginseng         return 1; -     } the } +  A  the voidSearchintXintDepDoubleLen) { +     if(Len>=ans)return; -     if(!look_up_table (len))return; $     if(dep==N) { $ans=min (len,ans); -         return; -     } thevis[x]=1; - //puts ("$");Wuyi      for(intI=0; I<g[x].size (); i++){ the         intnow=G[x][i]; -         if(!vis[now]) search (now,dep+1, len+c[x][i]); Wu     } -      Aboutvis[x]=0; $ } -  - intMain () { - //freopen ("01.in", "R", stdin); Ascanf"%d",&N); +      for(intI=1; i<=n;i++){ theCin>>nod[i].x>>nod[i].y; -         //scanf ("%lf", &nod[i].x,&nod[i].y); $     } thenod[0].x=nod[0].y=0.0; the      for(intI=0; i<=n;i++){ the          for(intj=i+1; j<=n;j++){ the G[i].push_back (j); - c[i].push_back (DIS (i,j)); in              the G[j].push_back (i); the c[j].push_back (DIS (i,j)); About         } the     } theSearch0,0,0.0); theprintf"%.2LF", ans); +     return 0; -}

90 points of map>_<

It's a map, and it's unexpected.

Hash does not seem to be possible, because their data are not over, there is no submission

As for the evaluation of the time I think the direct STL is good, hash try it

I was speechless when I saw the answer.

Backtracking and pruning.

1#include <iostream>2#include <cstring>3#include <cstdio>4#include <vector>5#include <cmath>6#include <map>7#include <algorithm>8 #defineINF 0x3f3f3f3f9 using namespacestd;Ten  One intn,vis[ -]; A Doubleans=INF; -  - structcc{ the     Doublex, y; -}nod[ -]; -  - DoubleDisintAintb) { +     returnsqrt ((nod[a].x-nod[b].x) * (nod[a].x-nod[b].x) + (NOD[A].Y-NOD[B].Y) * (nod[a].y-nod[b].y)); - } +  A voidSearchintXintDepDoubleLen) { at     if(Len>=ans)return; -     if(dep==N) { -ans=min (len,ans); -         return; -     } -      in      for(intI=1; i<=n;i++){ -         if(i==x)Continue; to         if(!Vis[i]) { +vis[i]=1; -Search (i,dep+1, len+dis (x,i)); thevis[i]=0; *         } $     }Panax Notoginseng      - } the  + intMain () { A //freopen ("01.in", "R", stdin); thescanf"%d",&N); +      for(intI=1; i<=n;i++) cin>>nod[i].x>>nod[i].y; -Search0,0,0.0); $printf"%.2LF", ans); $     return 0; -}

Finished?

All right, computer scum, 13-point data.

Rokua P1433 eating cheese Label:dfs && pruning ex