[Internet interview] questions about the circle of friends

Problem description:

If we know that there are n people and m friends (stored in the number R ). If two people are friends directly or indirectly (friends of friends ...),

They think they belong to the same circle of friends,

Write a program to find the total number of friends in the N groups.

Suppose n = 5, M = 3,
R = {1, 2}, {2, 3}, {4, 5} indicates five people, 1 and 2 are friends, and 2 and 3 are friends, 4 and 5 are friends,

Then 1, 2, 3 belong to one circle of friends, 4, 5 belong to another circle of friends, and the result is two circle of friends.

Finally, analyze the time and space complexity of the Code. The score will refer to the Code correctness and efficiency.

It is said that the query set is used to solve the problem .... I don't understand the code ......

 

// Circle of friends # include <iostream> using namespace STD; int set [10001]; // The Inline int find (int x) Search Algorithm with Path Optimization) {int I, j, R; r = x; while (set [R]! = R) {r = set [R];} I = x; while (I! = R) {J = set [I]; set [I] = r; I = J;} return r ;} // optimize and query the inline void merge (int x, int y) {int T = find (x); int H = find (y ); if (T