CodeForces - 731C~Socks（并查集+STL）

C. Socks

time limit per test
2 seconds

memory limit per test
256 megabytes

input
standard input

output
standard output

Arseniy is already grown-up and independent. His mother decided to leave him alone for m days and left on a vacation. She have prepared
a lot of food, left some money and washed all Arseniy's clothes.

Ten minutes before her leave she realized that it would be also useful to prepare instruction of which particular clothes to wear on each of the days she will be absent. Arseniy's family is a bit weird so all the clothes is enumerated. For example, each of
Arseniy's n socks is assigned a unique integer from 1 to n.
Thus, the only thing his mother had to do was to write down two integers li and ri for
each of the days — the indices of socks to wear on the day i (obviously, li stands
for the left foot and ri for
the right). Each sock is painted in one of kcolors.

When mother already left Arseniy noticed that according to instruction he would wear the socks of different colors on some days. Of course, that is a terrible mistake cause by a rush. Arseniy is a smart boy, and, by some magical coincidence, he posses k jars
with the paint — one for each of k colors.

Arseniy wants to repaint some of the socks in such a way, that for each of m days he can follow the mother's instructions and wear
the socks of the same color. As he is going to be very busy these days he will have no time to change the colors of any socks so he has to finalize the colors now.

The new computer game Bota-3 was just realised and Arseniy can't wait to play it. What is the minimum number of socks that need their color to be changed in order to make it possible to follow mother's instructions and wear the socks of the same color during
each of m days.

Input

The first line of input contains three integers n, m and k (2 ≤ n ≤ 200 000, 0 ≤ m ≤ 200 000, 1 ≤ k ≤ 200 000) —
the number of socks, the number of days and the number of available colors respectively.

The second line contain n integers c1, c2,
..., cn (1 ≤ ci ≤ k) —
current colors of Arseniy's socks.

Each of the following m lines contains two integers li and ri (1 ≤ li, ri ≤ n, li ≠ ri) —
indices of socks which Arseniy should wear during the i-th day.

Output

Print one integer — the minimum number of socks that should have their colors changed in order to be able to obey the instructions and not make people laugh from watching the socks of different colors.

Examples

input

3 2 3
1 2 3
1 2
2 3

output

2

input

3 2 21 1 21 22 1

output

0

Note

In the first sample, Arseniy can repaint the first and the third socks to the second color.

In the second sample, there is no need to change any colors.

注释应该写的很清楚了

#include<stdio.h>
#include<iostream>
#include<string.h>
#include<map>
#include<vector>
#define M 200005
using namespace std;
vector<int> v[M];
int n,m,k;
int a[M],f[M];
void init()
{
for(int i=1;i<=n;i++)
f[i]=i;
}
int getf(int x)
{
if(f[x]==x)return x;
f[x]=getf(f[x]);
return f[x];
}
void mix(int x,int y)
{
int tx=getf(x);
int ty=getf(y);
if(tx!=ty)
{
f[tx]=ty;
}
}
int main()
{
cin>>n>>m>>k;
init();
for(int i=1;i<=n;i++)
cin>>a[i];
int x,y;
for(int i=1;i<=m;i++)
{
cin>>x>>y;
//将每天需要穿的袜子放在相同的集合中
mix(x,y);
}
for(int i=1;i<=n;i++)
{
v[getf(i)].push_back(a[i]);
//用vector将结点之间的关系联系起来
}
int ans=0;
for(int i=1;i<=n;i++)
{
//由于每个根节点必会连自己本身，<=1直接跳过
if(v[i].size()<=1)
continue;
map<int,int>mp;
int maxx=0;
for(int j=0;j<v[i].size();j++)
{
//寻找此根节点中，相同颜色的袜子最多有几个
mp[v[i][j]]++;
maxx=max(maxx,mp[v[i][j]]);
}
//将其他颜色的袜子颜色都变为最大的，然后统计一下数量
ans+=v[i].size()-maxx;
}
printf("%d\n",ans);

}