3372448_ac_16ms_296k.cc

来自「北大大牛代码 1240道题的原代码 超级权威」· CC 代码 · 共 57 行

#include <stdio.h>
#include <string.h>

int map[26][26];
int used[26][26];
int max;
int n, m;

void dfs(int u, int deep)
{
	int mark = 0;

	for (int i = 0; i < n; i++)
	{
		if (map[u][i] == 1)
		{
			mark = 1;
			map[u][i] = map[i][u] = 0;
			dfs(i, deep + 1);
			map[u][i] = map[i][u] = 1;
		}
	}
	if (mark == 0)
	{
		if (deep > max)
		{
			max = deep;
		}
	}
}

int main()
{
	while (scanf("%d%d", &n, &m) == 2)
	{
		if (m == 0 && n == 0)
		{
			break;
		}
		memset(map, 0, sizeof(map));
		memset(used, 0, sizeof(used));
		int u, v;
		for (int i = 0; i < m; i++)
		{
			scanf("%d%d", &u, &v);
			map[u][v] = map[v][u] = 1;
		}
		max = 0;
		for (int i = 0; i < n; i++)
		{
			dfs(i, 0);
		}
		printf("%d\n", max);
	}
	return 0;
}