ZOJ 2048 Highways

N-Highways
TimeLimit:5000MSMemoryLimit:32768KB64bitIOFormat:%lld&%llu
SubmitStatus
Appointdescription:

Description
TheislandnationofFlatopiaisperfectlyflat.Unfortunately,Flatopiahasaverypoorsystemofpublichighways.TheFlatopiangovernmentisawareofthisproblemandhasalreadyconstructedanumberofhighwaysconnectingsomeofthemostimportanttowns.However,therearestillsometownsthatyoucan'treachviaahighway.Itisnecessarytobuildmorehighwayssothatitwillbepossibletodrivebetweenanypairoftownswithoutleavingthehighwaysystem.

Flatopiantownsarenumberedfrom1toNandtownihasapositiongivenbytheCartesiancoordinates(xi,yi).Eachhighwayconnectsexacltytwotowns.Allhighways(boththeoriginalonesandtheonesthataretobebuilt)followstraightlines,andthustheirlengthisequaltoCartesiandistancebetweentowns.Allhighwayscanbeusedinbothdirections.Highwayscanfreelycrosseachother,butadrivercanonlyswitchbetweenhighwaysatatownthatislocatedattheendofbothhighways.

TheFlatopiangovernmentwantstominimizethecostofbuildingnewhighways.However,theywanttoguaranteethateverytownishighway-reachablefromeveryothertown.SinceFlatopiaissoflat,thecostofahighwayisalwaysproportionaltoitslength.Thus,theleastexpensivehighwaysystemwillbetheonethatminimizesthetotalhighwayslength.

Input

Theinputconsistsoftwoparts.Thefirstpartdescribesalltownsinthecountry,andthesecondpartdescribesallofthehighwaysthathavealreadybeenbuilt.

ThefirstlineoftheinputcontainsasingleintegerN(1<=N<=750),representingthenumberoftowns.ThenextNlineseachcontaintwointegers,xiandyiseparatedbyaspace.Thesevaluesgivethecoordinatesofithtown(forifrom1toN).Coordinateswillhaveanabsolutevaluenogreaterthan10000.Everytownhasauniquelocation.

ThenextlinecontainsasingleintegerM(0<=M<=1000),representingthenumberofexistinghighways.ThenextMlineseachcontainapairofintegersseparatedbyaspace.Thesetwointegersgiveapairoftownnumberswhicharealreadyconnectedbyahighway.Eachpairoftownsisconnectedbyatmostonehighway.

Output

Writetotheoutputasinglelineforeachnewhighwaythatshouldbebuiltinordertoconnectalltownswithminimalpossibletotallengthofnewhighways.Eachhighwayshouldbepresentedbyprintingtownnumbersthatthishighwayconnects,separatedbyaspace.

Ifnonewhighwaysneedtobebuilt(alltownsarealreadyconnected),thentheoutputshouldbecreatedbutitshouldbeempty.

Thisproblemcontainsmultipletestcases!

ThefirstlineofamultipleinputisanintegerN,thenablanklinefollowedbyNinputblocks.Eachinputblockisintheformatindicatedintheproblemdescription.Thereisablanklinebetweeninputblocks.

TheoutputformatconsistsofNoutputblocks.Thereisablanklinebetweenoutputblocks.

SampleInput

1

9
15
00
32
45
51
04
52
12
53
3
13
97
12

SampleOutput

16
37
49
57
83

//求最小生成树将新加入的边的2个端点输出来

#include<iostream>
#include<stdio.h>
#include<queue>
#include<stack>
#include<set>
#include<vector>
#include<math.h>
#include<string.h>
#include<algorithm>
usingnamespacestd;
#defineN755
doubledis(doublex,doubley,doublea,doubleb)
{
returnsqrt((x-a)*(x-a)+(y-b)*(y-b));
}
doubled[N][2];
doublemap[N][N];
boolb[N];
doubleds[N];
intf[N],n;
voidPrim()
{
inti,k;
memset(b,0,sizeof(b));
doubleMin;
intt=n;
while(--t)
{
Min=1000000;
for(i=2;i<=n;i++)
if(!b[i]&&Min>ds[i])
{
Min=ds[i];
k=i;
}
b[k]=1;
for(i=2;i<=n;i++)
if(!b[i]&&map[k][i]<ds[i])
{
f[i]=k;
ds[i]=map[k][i];
}
}
}
intmain()
{
intT;
boolfl=0;
inti,j,k,m;
scanf("%d",&T);
while(T--)
{
if(fl)printf("\n");elsefl=true;
scanf("%d",&n);
for(i=1;i<=n;i++)
scanf("%lf%lf",&d[i][0],&d[i][1]),f[i]=1;
for(i=1;i<=n;i++)
for(j=i+1;j<=n;j++)
map[i][j]=map[j][i]=dis(d[i][0],d[i][1],d[j][0],d[j][1]);
scanf("%d",&m);
for(i=1;i<=m;i++)
{
scanf("%d%d",&j,&k);
map[j][k]=map[k][j]=0;
}
for(i=1;i<=n;i++)
ds[i]=map[1][i];
Prim();
for(i=2;i<=n;i++)
if(map[i][f[i]]!=0)
printf("%d%d\n",i,f[i]);
}
return0;
}