links[i].redrouter = new RedRouter((int)links[i].minth, 									   (int)links[i].maxth,									   links[i].pmax);					assert(links[i].red);									}				else{					links[i].red=0;				}								links[i].nflows = 0; // init the num of flows								continue;							}						assert(0);		}				// Check whether everything is all right 		assert (nConnections > 0);		assert (nLinks > 0);		for (int i=0; i<nConnections; ++i)			assert(nAdj[i] > 0);		  	}	double redFn(double minth, double pmin,		     double maxth, double pmax, double qlength){		assert(qlength>=0 && qlength<=1);		assert(pmax>=0 && pmax<=1);		assert(pmin>=0 && pmin<=1);		assert(minth>=0 && minth<=1);		assert(maxth>=0 && maxth<=1);		assert(maxth>=minth);		assert(pmax>pmin);			double t;		if(qlength<minth)			return 0;		if(qlength>maxth)			return 1;		return pmin + (qlength-minth)/(pmax-pmin);		}	void  CalcLinkStats(int flag = 0){			// flag = 1 means enable RED			// Calculate Link delays ... basically queuing delays			for(int i=0; i<nLinks; i++){					double rho = links[i].lambda/links[i].mu;			double qlength = Lq(rho,links[i].buffer);					links[i].qdelay = qlength/links[i].mu; 			links[i].drop = Pk(rho,links[i].buffer,links[i].buffer);			// cout << "Link " << i << " has drop prob = " << links[i].drop << endl;			// Special code for RED gateways			if(flag){				if(links[i].red){					double minth, maxth, pmin, pmax, delay,p;					minth = links[i].minth;					maxth = links[i].maxth;					pmin = links[i].pmin;					pmax = links[i].pmax;					// The RED approx.					p=(links[i].redrouter)->ComputeProbability(rho, delay);					links[i].drop = p;					qlength = Lq(rho*(1-p), links[i].buffer);					links[i].qdelay = delay;				}			}//			cout << i << sp << "rho = " << rho << " delay = " << links[i].qdelay << " and drop = " << links[i].drop << endl;		}		}	void CalcPerFlowStats(){ 		for(int i=0; i<nConnections; i++){			double d = 0, p = 1 ;			// Calculate drops and delays			for(int j=0;j<nAdj[i];j++){				d += 2*links[Adj[i][j]].prop + links[Adj[i][j]].qdelay;				p *= 1-links[Adj[i][j]].drop;			}			p = 1-p;			//cout << "Flow " << i << " has drop prob = " << p << endl; 					flows[i].no = nAdj[i];			flows[i].delay = d;			flows[i].drop = p;			flows[i].t = flows[i].p_tput;    					// p is the end2end drop prob			// If its normal flow, calculate Padhye's stuff			// If its short flow, use our approximations			// Nothing more							if(flows[i].is_sflow==1){				// If k flows come and each each flow has n packets to 				// send then 				double t = (flows[i].slambda*flows[i].snopkts);				flows[i].p_tput = t/(1-p);			}			else if(flows[i].is_sflow==2){				// For CBR, dont divide by 1-p unlike short flows.				// If rate is x and prob is p, net goodput is x(1-p)				flows[i].p_tput = flows[i].slambda*(1-p);				// cout << "cbr stuff - tput = " << flows[i].p_tput << endl;			}			else{				// regular bulk TCP connections, Padhye et. al.				if(!p){				// cout << "Oops, something wrong";				}				flows[i].p_tput = padhye(d,p);			}					// cout << "connection " << sp << i << sp << d << sp << p; 			//cout << sp << flows[i].p_tput << endl;						}	}	void PrintData(){		for(int i=0;i<nLinks;i++){			cout << i << sp << links[i].lambda << sp << links[i].mu;			cout << sp << links[i].buffer << endl;		}	}	void PrintResults(){			for(int i=0;i<nLinks;i++){			printf("l %d qdel %.5lf drop %.5lf lam %.3lf\n", i+1, links[i].qdelay, links[i].drop,links[i].lambda);		}			for(int i=0; i<nConnections; i++){			printf("c %d gput %.5lf drop %.5lf e2edel %.5lf\n", i+1,			       flows[i].p_tput,			       flows[i].drop,			       flows[i].delay);		}		}	void UpdateHelper(int flag=0){		// if flag = 1 then update only when link is unscaled as of now		// if flag = 0 then do the usual update 		for(int i=0; i<nLinks; i++){			links[i].tlambda=0;		}		for(int i=0; i<nConnections; i++){			if(!flag || !flows[i].scaled) 				for(int j=0;j<nAdj[i];j++){					if(flows[i].is_sflow==2){						// cbr flow						links[Adj[i][j]].tlambda += flows[i].slambda*(1-links[Adj[i][j]].drop);						//cout << "cbr flow " << i << " adding " << flows[i].slambda*(1-links[Adj[i][j]].drop)						//    << " to link " << j << " tlam = " << links[Adj[i][j]].tlambda << endl;					}					else						links[Adj[i][j]].tlambda += flows[i].p_tput;				}			//    cout << flows[i].p_tput << "\n";		}			}	void Update(int niter){		UpdateHelper();				for(int i=0; i<nLinks; i++){			links[i].plambda = links[i].lambda;			double t;			double tk=links[i].mu*(1.05)+5;					if(niter){				if(links[i].tlambda>tk)				//t = pow((sqrt(links[i].lambda)+sqrt(links[i].mu+5))/2,2);					t = ((links[i].lambda)+tk)/2;				// t = exp((log(links[i].lambda)+log(links[i].mu+5))/2);				else				//t = pow((sqrt(links[i].tlambda)+sqrt(links[i].lambda))/2,2);					t= ((links[i].tlambda)+(links[i].lambda))/2;				// t = exp((log(links[i].tlambda)+log(links[i].lambda))/2);			}			else t = links[i].tlambda;			links[i].lambda = t; // Update the lambda ..........		}	}	int allscaled(){		//cout << nConnections;		for(int i=0; i<nConnections; i++)			if(!flows[i].is_sflow && !flows[i].scaled){				//cout << "Connection " << i << " not scaled as yet\n";				return 0;			}		cout << "All are scaled\n";		return 1;	}  	void newupdate(int niter){		// 1st init all unscaled tputs and cap		for (int i=0;i<nLinks;i++){			links[i].uc = links[i].mu*(1.05);			links[i].utput = 0;		}		// calc all the unscaled tputs and C set all short flows 		// to be scaled already 		for(int i=0; i<nConnections; i++){			if(flows[i].is_sflow)				flows[i].scaled = 1;			else 				flows[i].scaled = 0;			for(int j=0;j<nAdj[i];j++){				if(flows[i].is_sflow)					links[Adj[i][j]].uc -= flows[i].p_tput;				else					links[Adj[i][j]].utput += flows[i].p_tput;			}		}		//for(int i =0; i<nLinks; i++ ){			//cout << i << sp << links[i].uc << sp << links[i].utput << endl;		//}		double maxgamma; // most congested link		int bneck;		double t;		bneck = -1;		maxgamma = 0;		for(int i=0; i<nLinks; i++){			if(links[i].uc){				t=links[i].utput/links[i].uc;				if(t > maxgamma){					bneck = i;					maxgamma = t;				}			}		}    		while(bneck+1){			//cout << "bneck = " << bneck << sp << links[bneck].uc << sp << links[bneck].utput << sp << maxgamma << sp << links[bneck].nflows <<endl;			for(int i=0; i<links[bneck].nflows; i++){				// For all the connections passing through this link				int t = links[bneck].theflows[i]; // get a connection id				//     cout << i<< sp << t << sp ;				// Now reduce its p_tput iff its not a short flow				// For short flows we dont do scaling				if(!flows[t].is_sflow && !flows[t].scaled){					flows[t].p_tput /= maxgamma;				//cout << "Flow " << t << " getting scaled to  << " << flows[t].p_tput;					flows[t].scaled = 1; // we have scaled this flow already					for(int j=0;j<nAdj[t];j++){						// subtract this scaled throughout from all teh links that						// have this flow. 						links[Adj[t][j]].uc -= flows[t].p_tput;						links[Adj[t][j]].utput -= flows[t].p_tput*maxgamma;						// cout << sp << Adj[i][j];					}				//cout << endl;				}			}    			//cout << links[bneck].uc << sp << links[bneck].utput << endl;    			links[bneck].uc = 0;			bneck = -1;			maxgamma = 0;			for(int i=0; i<nLinks; i++){				if(links[i].uc){					t=links[i].utput/links[i].uc;					if(t > maxgamma){						bneck = i;						maxgamma = t;					}				}			} 		}		Update(niter);	}	asim(){		//cout << "Reached here\n";	}};int main(int argc, char **argv) {	int niter = 0;	// error if usage is wrong 		   	if (argc != 2) {		fprintf(stderr,"Usage: %s  <InputFile>\n", argv[0]);		exit(-1); 	}		asim sim;	sim.GetInputs(argv[1]);	//sim.PrintResults();	//cout << "Read the input .... \n";	for(int i=0; i<3; i++){		sim.CalcLinkStats(1);		//cout << "Calculated link delays ... \n";		sim.CalcPerFlowStats();		//cout << "Calculated per flow delays ... \n";		//cout << " ------------------------------\n";		sim.newupdate(niter);		//sim.PrintResults();		//cout << " ------------------------------\n"; 	}	sim.PrintResults();}