标签:int 分享图片 两种 target strong http tar cstring ++
Time Limit: 1000MS | Memory Limit: 10000K | |
Total Submissions: 93264 | Accepted: 28135 |
Description
Input
Output
Sample Input
100 7 1 101 1 2 1 2 2 2 3 2 3 3 1 1 3 2 3 1 1 5 5
Sample Output
3
Source
http://poj.org/problem?id=1182
一道经典的并查集题目
这是用带权并查集做的代码
1 #include<iostream> 2 #include<cstdio> 3 #include<cmath> 4 #include<cstring> 5 #include<algorithm> 6 #include<string> 7 #include<queue> 8 #include<vector> 9 #include<set> 10 using namespace std; 11 12 int n,k; 13 int fa[50005]; 14 int dis[50005]; 15 16 int Find(int x){ 17 if(x!=fa[x]){ 18 int xx=fa[x]; 19 fa[x]=Find(fa[x]); 20 dis[x]=(dis[x]+dis[xx])%3; 21 } 22 return fa[x]; 23 } 24 25 int main(){ 26 27 int n,k; 28 ///0表示同类,1表示x吃y,2表示y吃x 29 scanf("%d %d",&n,&k); 30 for(int i=1;i<=n;i++){ 31 fa[i]=i; 32 dis[i]=0; 33 } 34 int ans=0; 35 int pos,x,y; 36 for(int i=1;i<=k;i++){ 37 scanf("%d %d %d",&pos,&x,&y); 38 if(pos==2&&x==y){ 39 ans++; 40 } 41 else if(x>n||y>n){ 42 ans++; 43 } 44 else{ 45 if(pos==1){///同类 46 if(Find(x)==Find(y)){///在一个并查集中 47 if(dis[x]!=dis[y]){ 48 ans++; 49 } 50 } 51 else{ 52 dis[fa[x]]=(dis[y]-dis[x]+3)%3; 53 fa[fa[x]]=fa[y]; 54 } 55 } 56 else{///x吃y 57 if(Find(x)==Find(y)){ 58 if(dis[x]!=(dis[y]+1)%3){ 59 ans++; 60 } 61 } 62 else{ 63 dis[fa[x]]=(dis[y]-dis[x]+4)%3; 64 fa[fa[x]]=fa[y]; 65 } 66 67 } 68 } 69 } 70 printf("%d\n",ans); 71 }
这是用种类并查集做的代码
1 #include<iostream> 2 #include<cstdio> 3 #include<cmath> 4 #include<cstring> 5 #include<algorithm> 6 #include<string> 7 #include<queue> 8 #include<vector> 9 #include<set> 10 using namespace std; 11 12 int n,k; 13 int fa[50005*3]; 14 15 int Find(int x){ 16 int r=x,y; 17 while(x!=fa[x]){ 18 x=fa[x]; 19 } 20 while(r!=x){ 21 y=fa[r]; 22 fa[r]=x; 23 r=y; 24 } 25 return x; 26 } 27 28 int main(){ 29 30 scanf("%d %d",&n,&k); 31 int ans=0; 32 for(int i=1;i<=n*3;i++){ 33 fa[i]=i; 34 } 35 int pos,x,y; 36 for(int i=1;i<=k;i++){ 37 scanf("%d %d %d",&pos,&x,&y); 38 if(x>n||y>n) { 39 ans++; 40 continue; 41 } 42 if(pos==1){///同类 43 if(Find(x)==Find(y+n)||Find(y)==Find(x+n)) ans++; 44 else{ 45 fa[Find(x)]=Find(y); 46 fa[Find(x+n)]=Find(y+n); 47 fa[Find(x+n+n)]=Find(y+n+n); 48 } 49 } 50 else{///x吃y 51 if(x==y){ 52 ans++; 53 } 54 else{ 55 if(Find(x)==Find(y)||Find(x+n)==Find(y)) ans++; 56 else{ 57 fa[Find(x)]=Find(y+n); 58 fa[Find(x+n)]=Find(y+n+n); 59 fa[Find(x+n+n)]=Find(y); 60 } 61 } 62 } 63 } 64 printf("%d\n",ans); 65 }
标签:int 分享图片 两种 target strong http tar cstring ++
原文地址:https://www.cnblogs.com/Fight-sh/p/9693745.html