PTA 5-7 (Chinese) Six-degree space (30)-figure-BFS

The "six-degree space" theory is also called the "six-degree separation (Six Degrees of Separation)" theory. This theory can be described in layman's words: "You and any stranger will not be more than six people, that is, up to five people you can know any stranger." As shown in "6.4.

Figure 6.4 Six-degree space

If you are given a social network diagram, calculate the percentage of nodes that correspond to the six-degree space theory for each node.

Input Format Description:

Enter line 1th to give two positive integers, representing the number of nodes in the social network graph N (1<n<=104, number of people), the number of sides m (<=33*n, which represents the social relationship). The subsequent M-line corresponds to the M-bar, and each row gives a pair of positive integers, each of which is the number of the two nodes directly connected to the bar (the node is numbered from 1 to n).

Output Format Description:

The percentage of the total number of nodes that each node output is not more than 6 from the node, and is accurate to 2 digits after the decimal point. Each node outputs a row in the form "node number: (space) percent%".

Input Sample:

10 91 22 33 44 55 66 77 88 99 10

Sample output:

1: 70.00%2: 80.00%3: 90.00%4: 100.00%5: 100.00%6: 100.00%7: 100.00%8: 90.00%9: 80.00%10: 70.00%

parsing: []

Code:

 #include <iostream> #include <fstream> #include <cstdio> #include <queue> #include <vector >using namespace Std;const int maxn=10005;int vertices, edges;vector<int> g[maxn];// The elements of each vector structure are represented: nodes with edges represented by an array subscript have a node bool VIS[MAXN]; Whether to access the int BFS (int v) {for (int i=0; i<maxn; i++) vis[i]=false;int tail;//to record the node int last=v per lamination; Record the last element of each layer: the last=temp is updated before it pops up: int count=1;int level=0;vis[v]=true;queue<int> Q;q.push (v); Q.empty ()) {int X=q.front ();//Eject x Q.pop (); for (int j=0; j<g[x].size (); j + +)//x a lap in the queue {if (!vis[g[x][j]])// If not accessed: Access and press into queue {Vis[g[x][j]]=true;q.push (g[x][j]); tail=g[x][j];//record the Node count++;}}    if (x==last)//Layer all pops up, ready to start playing the next layer: popup (x) = The last element of the current layer {last=tail; After the first layer is all pressed, update the last level++; }if (level==6) break; return count;} 

int main (int argc, char** argv) {int x,y;cin >> vertices >> edges;//ifstream fin ("test.txt");//fin >> ve Rtices >> edges;for (int i=1; i<=edges; i++) {cin >> x >> y;//fin >> x >> y; G[x].push_back (y); G[y].push_back (x);} for (int j=1; j<=vertices; J + +) {//cout << BFs (j) << endl;printf ("%d:%.2lf%%\n", J, BFs (j) *1.0/vertices* 100.0); Format output}return 0;}

PTA 5-7 (Chinese) Six-degree space (30)-figure-BFS