POJ Cube Stacking
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
題目大意:有N個立方體和N個格子,1~N編號,一開始i立方體在i號格子上,每個格子剛好1個立方體。現在m組操作,M a b表示將a號立方體所在的格子的全部立方體放在b號立方體所在的格子的全部立方體上面。C x表示詢問x號立方體下面的立方體的個數。
#include<cstdio> #include<string> #include<cstring> #include<vector> #include<algorithm> #include<iostream> using namespace std; const int N = 3e4 + 10; int p[N]; int s[N];//代表 在這個方格的總共的立方體數 int cnt[N];//代表 i 下面的立方體數 int findth(int x) { if (x != p[x]) { int t = p[x]; p[x] = findth(p[x]); cnt[x] += cnt[t];//路徑壓縮 } return p[x]; } void unionn(int x, int y) { int xx = findth(x); int yy = findth(y); if (xx != yy) { p[xx] = yy; cnt[xx] = s[yy]; s[yy] += s[xx]; } } int main() { for (int i = 1;i <= N;i++) { p[i] = i; s[i] = 1; } int T; scanf("%d", &T); while (T--) { char t[5]; scanf("%s", t); if (t[0] == 'M'){ int x, y; scanf("%d %d", &x, &y); unionn(x, y); } else { int x; scanf("%d", &x); findth(x);//路徑壓縮 printf("%d\n", cnt[x]); } } return 0; }