Here is a code that creates Barabasi Albert model for any number of nodes for any number of degrees, the code fully compiles with g++ but shows error while compiling with icpc(intel c++ compiler). I am attaching the code with the error report with this post.
#include<bits/stdc++.h>
using namespace std;
int EMPTY = 0;
int connectionNumber = 0;
vector<unsigned> network[3000001];
//seed for the network to grow
void seed(int netmap1[],int netmap2[],int N)
{
connectionNumber = 0;
for(unsigned i=1;i<=N;i++)
{
for(unsigned j=1;j<=N;j++)
{
if(i!=j)
{
network[i].push_back(j);
}
if(j>i)
{
connectionNumber++;
netmap1[connectionNumber]=i;
netmap2[connectionNumber]=j;
}
}
}
}
//actual node building on the algorithm of barabasi albert model
//stores the connection of each node in netmap1 and netmap2
void BA(int netmap1[],int netmap2[],int N,int seedNumber, int m)
{
srand(time(NULL));
int concheck=0;
int a[m] = {};
int countm=0;
double totalpk,pk;
for(int i = seedNumber+1;i<=N;i++)
{
countm=0;
cout<<"connection given to : "<<i<<endl;
totalpk = 0.0;
for(int n=0;n<m;n++)
{
a[n]=0;
}
for(int l=1;l<i;l++)
{
totalpk += network[l].size();
}
for(int j = 1; ; j++)
{
concheck = 0;
double u = (double)rand()/RAND_MAX;
pk = 0.0;
for(int k=1;k<i;k++)
{
if(concheck==1) break;
pk += (double)(network[k].size())/totalpk;
if(u<pk)
{
concheck = 0;
for(int n=0;n<m;n++)
{
if(a[n]==k)
{
concheck = 1;
}
}
if(concheck==0)
{
a[countm]=k;
countm++;
network[k].push_back(i);
network[i].push_back(k);
connectionNumber++;
netmap1[connectionNumber]=k;
netmap2[connectionNumber]=i;
totalpk += 2;
break;
}
else continue;
}
}
if(countm==m)
{
break;
}
}
}
}
int findroot(int ptr[],int i)
{
if(ptr[i]<0) return i;
return ptr[i]=findroot(ptr,ptr[i]);
}
//does explosive percolation with newman-ziff algorithm
void explosivepercolation(int netmap1[],int netmap2[],int vertices, int run, int filenum, int m)
{
srand(time(NULL));
int A,B,C;
A = vertices;
B = run;
C = filenum;
string filename1;
filename1 = "maxclus_";
string filename2;
filename2 = "delmx_";
string filename3;
filename3 = "entropy_";
filename1 = filename1+to_string(A)+"node_"+to_string(m)+"M_"+to_string(B)+"ens_"+to_string(C)+".dat";
filename2 = filename2+to_string(vertices)+"node_"+to_string(m)+"M_"+to_string(run)+"ens"+to_string(filenum)+".dat";
filename3 = filename3+to_string(vertices)+"node_"+to_string(m)+"M_"+to_string(run)+"ens"+to_string(filenum)+".dat";
ofstream fout1,fout2,fout3;
int* random = NULL;
random = new int[connectionNumber+1];
double* maxclus = NULL;
maxclus = new double[connectionNumber+1];
double* delmx = NULL;
delmx = new double[connectionNumber+1];
double* entropycalc = NULL;
entropycalc = new double[connectionNumber+1];
for(int i=0;i<=connectionNumber;i++)
{
maxclus[i]=0;
delmx[i]=0;
entropycalc[i]=0;
}
for(int i=0;i<=connectionNumber;i++)
{
random[i] = i;
}
int* ptr = new int[vertices+1];
for(int i=0;i<vertices+1;i++) ptr[i]=0;
//here it starts percolating for number of runs to take ensemble average
for(int rx=1;rx<=run;rx++)
{
cout<<"run commencing : "<<rx<<endl;
for(int i=0;i<vertices+1;i++) ptr[i]=0;
int index=0,big=0,bigtemp=0,jump=0,en1=0,en2=0;
int node1=0,node2=0,node3=0,node4=0,nodeA=0,nodeB=0;
int clus1=0,clus2=0,clus3=0,clus4=0;
long double entropy = log(vertices);
random_shuffle(&random[1],&random[connectionNumber]);
for(int i=0;i<=vertices;i++) ptr[i] = EMPTY;
for(int i=1;i<=connectionNumber;i++)
{
if(i!=connectionNumber)
{
node1 = netmap1[random[i]];
node2 = netmap2[random[i]];
node3 = netmap1[random[i+1]];
node4 = netmap2[random[i+1]];
if(ptr[node1]==EMPTY) clus1 = 1;
else
{
int x = findroot(ptr,node1);
clus1 = -ptr[x];
}
if(ptr[node2]==EMPTY) clus2 = 1;
else
{
int b = findroot(ptr,node2);
clus2 = -ptr[b];
}
if(ptr[node3]==EMPTY) clus3 = 1;
else
{
int c = findroot(ptr,node3);
clus3 = -ptr[c];
}
if(ptr[node4]==EMPTY) clus4 = 1;
else
{
int d = findroot(ptr,node4);
clus4 = -ptr[d];
}
if(clus1*clus2<clus3*clus4)
{
nodeA = node1;
nodeB = node2;
int N1=connectionNumber;
int M1=i+1;
int u = M1 + rand()/(RAND_MAX/(N1-M1+1) + 1);
int temp = random[u];
random[u] = random[i+1];
random[i+1] = temp;
}
else
{
nodeA = node3;
nodeB = node4;
int temp = random[i+1];
random[i+1] = random[i];
random[i] = temp;
int N1=connectionNumber;
int M1=i+1;
int u = M1 + rand()/(RAND_MAX/(N1-M1+1) + 1);
temp = random[u];
random[u] = random[i+1];
random[i+1] = temp;
}
}
else
{
nodeA = netmap1[random[i]];
nodeB = netmap2[random[i]];
}
if(ptr[nodeA]==EMPTY && ptr[nodeB]==EMPTY)
{
en1=1;
en2=1;
ptr[nodeA] = -2;
ptr[nodeB] = nodeA;
index = nodeA;
entropy = (long double)(entropy-(-2.0/vertices*log(1.0/vertices))+(-2.0/vertices*log(2.0/vertices)));
if(entropy<0) entropy = 0;
}
else if(ptr[nodeA]==EMPTY && ptr[nodeB]!=EMPTY)
{
en1=1;
int e = findroot(ptr,nodeB);
en2 = -(ptr[e]);
ptr[nodeA] = e;
ptr[e] += -1;
index = e;
entropy = entropy-(-(double)1.0/vertices*log(1.0/(double)vertices))-(-(double)en2/vertices*log((double)en2/vertices))+(-( double)(-ptr[index])/vertices*log((-ptr[index])/(double)vertices));
if(entropy<0) entropy = 0;
}
else if(ptr[nodeA]!=EMPTY && ptr[nodeB]==EMPTY)
{
en2 = 1;
int f = findroot(ptr,nodeA);
en1 = -(ptr[f]);
ptr[nodeB] = f;
ptr[f] += -1;
index = f;
entropy = entropy-(-(double)1.0/(long double)vertices*log(1.0/(long double)vertices))-(-(double)en1/(long double)vertices*log((long double)en1/vertices))+(-(long double)(-ptr[index])/vertices*log((-ptr[index])/(long double)vertices));
if(entropy<0) entropy = 0;
}
else if(ptr[nodeA]!=EMPTY && ptr[nodeB]!=EMPTY)
{
int g,h;
g = findroot(ptr,nodeA);
en1 = -(ptr[g]);
h = findroot(ptr,nodeB);
en2 = -(ptr[h]);
if(g!=h)
{
if(ptr[g]<ptr[h])
{
ptr[g] += ptr[h];
ptr[h] = g;
index = g;
}
else
{
ptr[h] += ptr[g];
ptr[g] = h;
index = h;
}
entropy = entropy-(-(long double)en1/(long double)vertices*log((long double)en1/(long double)vertices))-(-(long double)en2/vertices*log((long double)en2/(long double)vertices))+(-(long double)(-ptr[index])/vertices*log((long double)(-ptr[index])/(long double)vertices));
if(entropy<0) entropy = 0;
}
else
{
jump=big-bigtemp;
maxclus[i] += big;
delmx[i] += jump;
if(entropy<0) entropy = 0;
entropycalc[i] += entropy;
bigtemp = big;
continue;
}
}
if(-ptr[index]>big) big = -ptr[index];
jump = big - bigtemp;
maxclus[i] += big;
delmx[i] += jump;
entropycalc[i] += entropy;
bigtemp = big;
}
}
fout1.open(filename1.c_str());
fout2.open(filename2.c_str());
fout3.open(filename3.c_str());
//saves the result of maxcluster, jump and entropy calculation to file
for(int i=1;i<=connectionNumber;i++)
{
fout1<<(double)i/connectionNumber<<'\t'<<(double)maxclus[i]/vertices/run<<endl;
fout2<<(double)i/connectionNumber<<'\t'<<(double)delmx[i]/run<<endl;
fout3<<(double)i/connectionNumber<<'\t'<<(double)entropycalc[i]/run<<endl;
}
fout1.close();
fout2.close();
fout3.close();
delete[] random;
random = NULL;
delete[] maxclus;
maxclus = NULL;
delete[] delmx;
delmx = NULL;
delete[] entropycalc;
entropycalc = NULL;
}
int main()
{
int a,b,c,d,e,f;
cout<<"enter seed size: ";
cin>>a;
cout<<endl;
cout<<"enter vertice number: ";
cin>>b;
cout<<endl;
cout<<"order number: ";
cin>>c;
cout<<endl;
cout<<"enter ensemble number: ";
cin>>d;
cout<<endl;
cout<<"enter filenumber: ";
cin>>e;
cout<<endl;
int con = 0;
for(int i=1;i<a;i++)
{
con = con + i;
}
con = con + (b-a)*c;
int* ntmp1 = new int[con+1];
int* ntmp2 = new int[con+1];
for(int i=1;i<=con;i++)
{
ntmp1[i] = 0;
ntmp2[i] = 0;
}
seed(ntmp1,ntmp2,a);
BA(ntmp1,ntmp2,b,a,c);
explosivepercolation(ntmp1,ntmp2,b,d,e,c);
delete [] ntmp1;
ntmp1 = NULL;
delete [] ntmp2;
ntmp2 = NULL;
return 0;
}
now the error it shows on icpc is
if any kind soul know how to fix this, please help me out.