备战NOIP——模板复习2
这里只有模板,并不作讲解,仅为路过的各位做一个参考以及用做自己复习的资料,转载注明出处。
并查集模板
路径压缩
/*Copyright: Copyright (c) 2018
*Created on 2018-10-28
*Author: 十甫
*Version 1.0
*Title: 并查集-路径压缩
*Time: 4 mins
*/
#include<cstdio>
#include<iostream>
using namespace std;
const int size = 10005;
int f[size];
inline int getf(int k) {
if(f[k] != k) f[k] = getf(f[k]);
return f[k];
}
inline void merge(int a, int b) {
int fa = getf(a), fb = getf(b);
if(fa == fb) return;
else f[fa] = fb;
}
inline void init(int n) {
for(int i = 1;i <= n;i++) {
f[i] = i;
}
}
int main() {
int n, m;
scanf("%d%d", &n, &m);
init(n);
while(m--) {
int man, a, b;
scanf("%d%d%d", &man, &a, &b);
if(man) {
merge(a, b);
} else {
int fa = getf(a), fb = getf(b);
if(fa == fb) printf("YES\n");
else printf("NO\n");
}
}
return 0;
}
路径压缩+伪·按秩合并
/*Copyright: Copyright (c) 2018
*Created on 2018-10-28
*Author: 十甫
*Version 2.0
*Title: 并查集-路径压缩+伪·按秩合并
*Time: 12 mins
*/
#include<cstdio>
#include<iostream>
#include<cstdlib>
#include<ctime>
using namespace std;
const int size = 10005;
int f[size];
inline int getf(int k) {
if(f[k] != k) f[k] = getf(f[k]);
return f[k];
}
inline void merge(int a, int b) {
int fa = getf(a), fb = getf(b);
if(fa == fb) return;
else {
if(rand() % 2) f[fa] = fb;
else f[fb] = fa;
}
}
inline void init(int n) {
srand(time(NULL));
for(int i = 1;i <= n;i++) {
f[i] = i;
}
}
int main() {
int n, m;
scanf("%d%d", &n, &m);
init(n);
while(m--) {
int man, a, b;
scanf("%d%d%d", &man, &a, &b);
if(man) {
merge(a, b);
} else {
int fa = getf(a), fb = getf(b);
if(fa == fb) printf("YES\n");
else printf("NO\n");
}
}
return 0;
}
NOIP 2018 RP++