Cube Stacking
Time Limit: 2000MS | Memory Limit: 30000K | |
Total Submissions: 24664 | Accepted: 8652 | |
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.
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.
* 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
思路:简单并查集,num[i]记录i点距离根节点多远,sum[i]记录i的儿子+自己数量。
# include <iostream> # include <cstring> # include <cstdio> # include <algorithm> # define MAXN 30000 using namespace std; int pre[MAXN+1], sum[MAXN+1], num[MAXN+1]; int find(int x) { if(x == pre[x]) return pre[x]; else { int t = pre[x]; pre[x] = find(pre[x]); num[x] = num[t] + num[x]; return pre[x]; } } int main() { int p, a, b; char c; while(~scanf("%d",&p)) { for(int i=1; i<=MAXN; ++i) { pre[i] = i; sum[i] = 1; num[i] = 0; } while(p--) { getchar(); c = getchar(); if(c == 'M') { scanf("%d%d",&a,&b); int px = find(a); int py = find(b); if(px != py) { pre[px] = py; num[px] = sum[py]; sum[py] += sum[px]; } } else { scanf("%d",&a); find(a); printf("%d\n",num[a]); } } } return 0; }