并查集 带压缩路径的版本

#include <iostream>

using

namespace

std;

typedef

struct

{

int

a,b;

}road;

const

int

MAX=5001;

int

N,M,K;

int

father[MAX];

int

rank[MAX];

road rd[500000];

void

make_set()

{

int

i;

for

(i=1;i<=N;i++)

{

father[i]=i;

rank[i]=0;

}

}

int

find_set(

int

x)

{

if

(x!=father[x])

father[x]=find_set(father[x]);

return

father[x];

}

void

union_set(

int

x,

int

y)

{

x=find_set(x);

y=find_set(y);

if

(x==y)

return

;

if

(rank[x]>rank[y])

father[y]=x;

else

{

father[x]=y;

if

(rank[x]==rank[y])

rank[y]++;

}

}

int

main()

{

cin>>N>>M>>K;

int

i,j;

int

start,end;

int

input;

for

(i=1;i<=M;i++)

{

cin>>start>>end;

rd[i].a=start;

rd[i].b=end;

}

for

(i=1;i<=K;i++)

{

int

cnt=-2;

cin>>input;

make_set();

for

(j=1;j<=M;j++)

{

if

(rd[j].a!=input && rd[j].b!=input)

union_set(rd[j].a,rd[j].b);

}

for

(j=1;j<=N;j++)

{

if

(father[j]==j)

cnt++;

}

cout<<cnt<<endl;

}

return

0;

}

/**************************************************************

Problem: 1325

User: feng345feng

Language: C++

Result: Accepted

Time:800 ms

Memory:5456 kb

****************************************************************/