学步园

  也没啥好说的，纯粹给自己复习下算法，赤裸裸的Floyd最短路。

#include <iostream>
using namespace std;

#define MAXVALUE 1<<29

int main()
{
	const int nNumber=20;
	int graphMat[nNumber+1][nNumber+1];
	int firstN;
	int nTest=0;

	while(cin>>firstN)
	{
		nTest++;
		//Initialize the matrix
		for(int i=1;i<=nNumber;i++)
			for(int j=1;j<=nNumber;j++)
			{
				graphMat[i][j]=MAXVALUE;
			}

			for(int i=1;i<=nNumber;i++)
			{
				graphMat[i][i]=0;
			}

		int neighbor;
		for(int ith=0;ith<firstN;ith++)
		{
			cin>>neighbor;
			graphMat[1][neighbor]=graphMat[neighbor][1]=1;
		}
		int ithNeighbor;
		for(int k=2;k<=19;k++)
		{
			cin>>ithNeighbor;
			for(int ith=0;ith<ithNeighbor;ith++)
			{
				cin>>neighbor;
				graphMat[k][neighbor]=graphMat[neighbor][k]=1;
			}
		}


		for(int k=1;k<=nNumber;k++)
		{
			for(int i=1;i<=nNumber;i++)
				for(int j=1;j<=nNumber;j++)
				{
					if(graphMat[i][j]>graphMat[i][k]+graphMat[k][j])
					{
						graphMat[i][j]=graphMat[i][k]+graphMat[k][j];
					}
				}
		}

		int nQuestion,nS,nE;
		cin>>nQuestion;
		cout<<"Test Set #"<<nTest<<endl;
		while(nQuestion>0)
		{
			nQuestion--;
			cin>>nS>>nE;
			//1 to 20: 
			cout<<nS<<" to "<<nE<<": "<<graphMat[nS][nE]<<endl;
		}
		cout<<endl;

	}
	
	return 0;

}