CodeForces 731C C - Socks 并查集
Description
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 k colors.
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.
Sample Input
3 2 3
1 2 3
1 2
2 3
2
3 2 2
1 1 2
1 2
2 1
0
Sample Output
Hint
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.
比较简单的并查集。
思路就是,因为它说[L, R]是同一个颜色。那就合并起来。
然后对于并查集的每段区间里面的数。都有各自的颜色,贪心去变成颜色出现最多那个就行了。
就是用并查集把他们分组了。
没一组都要相同颜色。那么本来有2号颜色是最多的话。那么其它都要变成2号颜色。
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <cmath>
#include <algorithm>
using namespace std;
#define inf (0x3f3f3f3f)
typedef long long int LL; #include <iostream>
#include <sstream>
#include <vector>
#include <set>
#include <map>
#include <queue>
#include <string>
const int maxn = + ;
int fa[maxn];
int colors[maxn];
vector<int>pos[maxn];
int find(int u) {
if (fa[u] == u) {
return fa[u];
} else return fa[u] = find(fa[u]);
}
void merge(int x, int y) {
x = find(x);
y = find(y);
if (x != y) {
fa[y] = x;
}
}
int book[maxn];
void work() {
for (int i = ; i <= maxn - ; ++i) fa[i] = i;
int n, m, k;
scanf("%d%d%d", &n, &m, &k);
for (int i = ; i <= n; ++i) {
scanf("%d", &colors[i]);
}
for (int i = ; i <= m; ++i) {
int L, R;
scanf("%d%d", &L, &R);
merge(L, R);
}
for (int i = ; i <= n; ++i) {
pos[find(i)].push_back(i);
}
int ans = ;
for (int i = ; i <= n; ++i) {
if (pos[i].size() == ) continue;
for (int j = ; j < pos[i].size(); ++j) {
book[colors[pos[i][j]]]++;
}
int mx = -inf;
for (int j = ; j < pos[i].size(); ++j) {
mx = max(book[colors[pos[i][j]]], mx);
book[colors[pos[i][j]]] = ;
}
// memset(book, 0, sizeof book);
ans += pos[i].size() - mx;
}
cout << ans << endl;
}
int main() {
#ifdef local
freopen("data.txt","r",stdin);
#endif
work();
return ;
}
CodeForces 731C C - Socks 并查集的更多相关文章
- Codeforces 731C Socks 并查集
题目:http://codeforces.com/contest/731/problem/C 思路:并查集处理出哪几堆袜子是同一颜色的,对于每堆袜子求出出现最多颜色的次数,用这堆袜子的数目减去该值即为 ...
- Codeforces 731C:Socks(并查集)
http://codeforces.com/problemset/problem/731/C 题意:有n只袜子,m天,k个颜色,每个袜子有一个颜色,再给出m天,每天有两只袜子,每只袜子可能不同颜色,问 ...
- Codeforces Round #376 (Div. 2) C. Socks —— 并查集 + 贪心
题目链接:http://codeforces.com/contest/731/problem/C 题解: 1.看题目时,大概知道,不同的袜子会因为要在同一天穿而差生了关联(或者叫相互制约), 其中一条 ...
- CF731C Socks并查集(森林),连边,贪心,森林遍历方式,动态开点释放内存
http://codeforces.com/problemset/problem/731/C 这个题的题意是..小明的妈妈给小明留下了n只袜子,给你一个大小为n的颜色序列c 代表第i只袜子的颜色,小明 ...
- Codeforces Gym 100463E Spies 并查集
Spies Time Limit: 20 Sec Memory Limit: 256 MB 题目连接 http://codeforces.com/gym/100463/attachments Desc ...
- Codeforces 859E Desk Disorder 并查集找环,乘法原理
题目链接:http://codeforces.com/contest/859/problem/E 题意:有N个人.2N个座位.现在告诉你这N个人它们现在的座位.以及它们想去的座位.每个人可以去它们想去 ...
- Codeforces - 828C String Reconstruction —— 并查集find()函数
题目链接:http://codeforces.com/contest/828/problem/C C. String Reconstruction time limit per test 2 seco ...
- 【25.23%】【codeforces 731C】Socks
time limit per test2 seconds memory limit per test256 megabytes inputstandard input outputstandard o ...
- Codeforces 571D - Campus(并查集+线段树+DFS 序,hot tea)
Codeforces 题目传送门 & 洛谷题目传送门 看到集合的合并,可以本能地想到并查集. 不过这题的操作与传统意义上的并查集不太一样,传统意义上的并查集一般是用来判断连通性的,而此题还需支 ...
随机推荐
- 3D Flip
<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8&quo ...
- 「JLOI2011」「LuoguP4568」飞行路线(分层图最短路
题目描述 Alice和Bob现在要乘飞机旅行,他们选择了一家相对便宜的航空公司.该航空公司一共在nn个城市设有业务,设这些城市分别标记为00到n-1n−1,一共有mm种航线,每种航线连接两个城市,并且 ...
- 实际用户ID和有效用户ID (三) *****
我们知道权限有r,w,x.其实除了这三个,还有特殊权限.比如: [root@localhost ~]# ls -l /usr/bin/passwd -rwsr-xr-x 1 root root 229 ...
- POJ3264(线段树入门题)
Balanced LineupCrawling in process... Crawling failed Time Limit:5000MS Memory Limit:65536KB ...
- <meta> 标记汇总
1. <meta name="viewport" content="width=device-width, initial-scale=1"> v ...
- Day05:装饰器,三元表达式,函数的递归,匿名/内置函数,迭代器,模块,开发目录
上节课复习:1.函数的对象 函数可以被当作数据取处理2.函数嵌套 嵌套调用:在调用一个函数时,函数体代码又调用了其他函数 嵌套定义:在一个函数内部又定义了另一个函数 def foo( ...
- 01_SQlite数据库简介
- CodeForces 1109F. Sasha and Algorithm of Silence's Sounds
题目简述:给定一个$n \times m$的二维矩阵$a[i][j]$,其中$1 \leq nm \leq 2 \times 10^5$,矩阵元素$1 \leq a[i][j] \leq nm$且互不 ...
- C#生成满足特定要求的密码
代码1 Random m_rnd = new Random(); public char getRandomChar() { ); || (ret > && ret < ) ...
- Laravel中使用Session存取验证码信息
1.将验证码存储到session中. $request->session()->put('validate_code',$validateCode->getCode());//存储信 ...