poj 1988Cube Stacking(並查集路徑壓縮 求本節點到父節點的結點數)
Cube Stacking
Time Limit: 2000MS | Memory Limit: 30000K | |
Total Submissions: 28664 | Accepted: 10067 | |
Case Time Limit: 1000MS |
Description
Farmer John and Betsy are playing a game with N (1 <= N <= 30,000)identical cubes labeled 1 through N. They start with N stacks, each containing a single cube. Farmer John asks Betsy to perform P (1<= P <= 100,000) operation. There are two types of operations: moves and counts. * In a move operation, Farmer John asks Bessie to move the stack containing cube X on top of the stack containing cube Y. * In a count operation, Farmer John asks Bessie to count the number of cubes on the stack with cube X that are under the cube X and report that value. Write a program that can verify the results of the game.
Input
* Line 1: A single integer, P * Lines 2..P+1: Each of these lines describes a legal operation. Line 2 describes the first operation, etc. Each line begins with a 'M' for a move operation or a 'C' for a count operation. For move operations, the line also contains two integers: X and Y.For count operations, the line also contains a single integer: X. Note that the value for N does not appear in the input file. No move operation will request a move a stack onto itself.
Output
Print the output from each of the count operations in the same order as the input file.
Sample Input
6 M 1 6 C 1 M 2 4 M 2 6 C 3 C 4
Sample Output
1 0 2
Source
把下面的看成父節點,但是並查集的每個節點維護3個變數:父節點編號father[i],其與父節點之間有多少個節點(不包括當前節點但包括父節點)v[i],以當前節點為根的連通分量一共有多少節點total[i]。
#include<iostream> #include<cstdio> #include<cstring> #include<algorithm> #define maxn 50005 int father[maxn]; int v[maxn]; int total[maxn]; using namespace std; int find(int x) { if(father[x]==x) return x; int root=find(father[x]); v[x]+=v[father[x]]; return father[x]=root; } void unionn(int x,int y) { int fa=find(x); int fb=find(y); if(fa!=fb) { father[fa]=fb; v[fa]=total[fb]; total[fb]+=total[fa]; } } int main() { int p; while(~scanf("%d",&p)&&p) { for(int i=0;i<=maxn;i++) {father[i]=i; total[i]=1; v[i]=0; } while(p--) { char str[10]; int a,b; scanf("%s",str); if(str[0]=='M') { scanf("%d%d",&a,&b); unionn(a,b); } else if(str[0]=='C') { scanf("%d",&a); find(a); printf("%d\n",v[a]); } } } return 0; }