# ZOJ 3396 Conference Call (3-point minimum spanning tree)

Source: Internet
Author: User

Test instructions: Gives a set of non-direction graphs with m points, and then gives N points, which are connected to a point in the graph with one edge respectively. For each query, find the minimum cost of 3-point connectivity. It is possible that 3 points are not interoperable. , the minimum price is the sum of the red side's weights.

Idea: First of the M-point of the non-direction of the diagram to find the shortest path between 22, with Floyd. Next, for each query, the poor lift m points, the sum of 3 points to the point of the distance, the minimum can be obtained.

`1 //#include <bits/stdc++.h>2#include <iostream>3#include <cstdio>4#include <cstring>5 #defineINB 0x7f7f7f7f6 using namespacestd;7 Const intn=10005;8 intTsf[n];//Telephone I received the transit station9 intgph;//adjacency matrix representation diagramTen  One intnexte;//auxiliary matrices for Floyd A intdis; -  -  the intCalintAintBintCintm) - { -     intSmall=INB; -      for(intk=1; k<=m; k++) +     { -         if(dis[a][k]==inb| | dis[b][k]==inb| | dis[c][k]==INB) +             Continue; A         if(dis[a][k]+dis[b][k]+dis[c][k]<small) atsmall=dis[a][k]+dis[b][k]+Dis[c][k]; -     } -     if(SMALL&GT;=INB)return 0; -     returnSmall; - } -  in voidFloydintm) - { tomemset (Nexte,0x80,sizeof(Nexte));//Initialize to negative +memset (DIS,0x7f,sizeof(dis));//Initialize to Infinity -  the     //initialize next for reachable *      for(intI=1; i<=m; i++) \$     {Panax Notoginseng          for(intj=1; j<=m; J + +) -         { the             if(I==J) dis[i][i]=0;//to their +             if(gph[i][j]>0)//If I to J have side A             { theNexte[i][j]=j;//this is the path matrix +DIS[I][J]=GPH[I][J];//graph without Direction -             } \$         } \$     } -  -      for(intk=1; k<=m; k++) the     { -          for(intI=1; i<=m; i++)Wuyi         { the              for(intj=1; j<=m; J + +) -             { Wu  -                 if(Dis[i][k]>=inb | | dis[k][j]>=inb)Continue;//paragraph two, one of which is already unreachable . About                 if(dis[i][j]>dis[i][k]+ Dis[k][j])//This is a shorter road . \$                 { -dis[i][j]=dis[i][k]+Dis[k][j]; -NEXTE[I][J]=NEXTE[I][K];//Modify Path -                 } A             } +         } the     } - } \$  the intMain () the { the     //freopen ("E://input.txt "," R ", stdin); the     intN, M, L, j=0; -     intA, B, V, q; in      while(cin>>n>>m>>l) the     { thememset (GPH,0,sizeof(GPH));//Initialize About          for(intI=0; i<n; i++)//Enter the broker to which the phone is connected thescanf"%d", &tsf[i+1]); the          for(intI=0; i<l; i++)//Enter a broker map the         { +scanf"%d%d%d",&a,&b,&v); -gph[a][b]=v; thegph[b][a]=v;Bayi         } theFloyd (M);//Freud start thescanf"%d",&q); -printf"Case #%d\n",++j); -          for(intI=0; i<q; i++)//Process each query the         { thescanf"%d%d%d",&a,&b,&v); the             intcn1=cal (tsf[a],tsf[b],tsf[v],m); the             if(ANS) -printf"Line %d:the minimum cost for this line is%d.\n", i+1, ans); the             Else theprintf"Line %d:impossible to connect!\n", i+1); the         }94     } the     return 0; the}`
AC Code

ZOJ 3396 Conference Call (3-point minimum spanning tree)

Related Keywords:

The content source of this page is from Internet, which doesn't represent Alibaba Cloud's opinion; products and services mentioned on that page don't have any relationship with Alibaba Cloud. If the content of the page makes you feel confusing, please write us an email, we will handle the problem within 5 days after receiving your email.

If you find any instances of plagiarism from the community, please send an email to: info-contact@alibabacloud.com and provide relevant evidence. A staff member will contact you within 5 working days.

## A Free Trial That Lets You Build Big!

Start building with 50+ products and up to 12 months usage for Elastic Compute Service

• #### Sales Support

1 on 1 presale consultation

• #### After-Sales Support

24/7 Technical Support 6 Free Tickets per Quarter Faster Response

• Alibaba Cloud offers highly flexible support services tailored to meet your exact needs.