uva-10305-水题-拓扑排序

Posted 2020-09-27 菜菜

输入n,m,n代表点数,m代表边数(i,j),排序时i在j前面,没出现的点随意排

#include <iostream>
#include<stdio.h>
#include<math.h>
#include<memory.h>
using namespace std;

const int maxNum = 120;
int a, b;
int map[maxNum][maxNum];
int vis[maxNum];
int index2;
int res[maxNum];
bool topoSort(int row)
{
	vis[row] = -1;
	for (int i = 1; i <= a; i++)
	{
		if (vis[i] == -1 && i != row)
			 continue;
		else if (map[row][i] == 1 && vis[i] == 0)
		{
			topoSort(i);
		}
	}
	res[++index2] = row;
	vis[row] = 1;
	return true;
}

int main()
{
	
	while (cin >> a >> b)
	{
		if(a == b && b == 0)
		{
			return 0;
		}
		index2 = 0;
		memset(map, 0, sizeof(map));
		memset(vis, 0, sizeof(vis));
		int j, k;
		for (int i = 0; i < b; i++)
		{
			cin >> j >> k;
			//前向边
			map[j][k] = 1;
		}

		for (int i = 1; i <= a; i++)
		{
			if (vis[i] == 0)
				topoSort(i);
		}
		for (int i = a; i >= 1; i--)
		{
			if (i == a)
			{
				cout << res[i];
				continue;
			}
			cout << " " << res[i];
		}
		cout << endl;
	}
	return 0;
}