PageRank algorithm C + + code implementation Standard Edition

For the PageRank algorithm, Wikipedia and many of the online blogs of Daniel have been described in detail, here is a self-written PageRank algorithm C + + implementation version:

/** Author:yang xiangyu* The Chinese University of Hong kong*/#include <cstdio> #include <iostream> #include <fstream> #include <cstdlib> #include <string> #include <algorithm>using namespace std; #define MAX 1000000struct edge//define edge{int u;int v;} Edge[5200000];int rednum[max]={0};//to Mark a point the if it has been visited, and record a new Numberint orinum[max]={0 };//to record the original number of the new recorded Numberint d[max]={0};//to mark the out degree of the pointdouble ra[ Max]={0};//to mark the current rank value of the pointdouble rb[max]={0};//to mark the updated rank value of the Pointint CMP (const int &AMP;A, const int &b) {if (Ra[rednum[a]]>ra[rednum[b]]) return 1;return 0;}  void Solve () {ifstream fin ("d:\\web-google.txt");//if TA want to test my code, click the text ' Web-google.txt ' to the D disk.ofstream fout ("D:\\output.txt"); memset (edge); string edge,0,sizeof (int s;for) {i=0;i<4;++i (getline) ; cout<<s<<endl;} Read the first four lines of the input fileint ncnt=0;int ecnt=0;int cnt=0;double eps=0.1;double flag;int i;for (i=0;fin& Gt;>edge[i].u>>edge[i].v;++i)//input the point of each edge{if (!REDNUM[EDGE[I].U])//judge the point Whether it has been visited {rednum[edge[i].u]=ncnt;//redefine the number of current pointorinum[ncnt++]=edge[i].u;// Record the original number of current point}if (!REDNUM[EDGE[I].V])//judge the point whether it had been visited{rednum[ed Ge[i].v]=ncnt;//redefine the number of current Pointorinum[ncnt++]=edge[i].v;//record the original number of current Poin t}d[rednum[edge[i].u]]++;} ecnt=i;printf ("%d%d\n", ncnt,ecnt); for (i=0;i<ncnt;++i) ra[i]= (double) 1/ncnt;while (eps>0.0000001)//setε=10^ (-7) {printf ("%d%.7lf\n", cnt,eps); eps=0;cnt++;for (int i=0;i<ecnt;++i) RB[REDNUM[EDGE[I].V]]+=RA[REDNUM[EDGE[I].U] /D[REDNUM[EDGE[I].U]]; First step to initialize the rank valuefor (int i=0;i<ncnt;++i) {rb[i]=rb[i]*0.8+ (0.2*1/ncnt);//add the random Jumpin G COefficientβ, and Setβ=0.8eps+=ra[i]>rb[i]? (Ra[i]-rb[i]):(rb[i]-ra[i])//compute The difference between the old rank value and new rank value, and update theεra[i]= rb[i];rb[i]=0;}} Sort (orinum,orinum+ncnt,cmp);//sort the array according to the scorefor (int i=0;i<100;++i) Fout<<orinum[i] << ' <<ra[rednum[orinum[i]]]<<endl;} int main () {solve (); return 0;}

PageRank algorithm C + + code implementation Standard Edition