dfs 变形课

#include<stdio.h>
#include<string.h>
#include<math.h>
#include<stdlib.h>
#include<algorithm>
#include<iostream>
#include<queue>
using namespace std;
struct node
{
	char head, end;
};
node incantation[10000];

char temp[20];
int i;
//int stratnum[10000];
bool can;
bool in_sign[10000];
void dfs(char k)
{


	if (k == 'm')
	{
		can = true;
		return;
	}

	for (int j = 0; j < i; j++)
	{
		if (incantation[j].head == k && in_sign[j] == false)
		{
			in_sign[j] = true;
			dfs(incantation[j].end);
			in_sign[j] = false;
		}
	}

}
int main()
{
		while (~scanf("%s", temp))
		{
			i = 0;
			if (!strcmp(temp, "0")) { continue; }
			can = false;
			incantation[i].head = temp[0];
			incantation[i++].end = temp[strlen(temp) - 1];
			while (scanf("%s", temp), strcmp(temp, "0"))
			{
				incantation[i].head = temp[0];
				incantation[i++].end = temp[strlen(temp) - 1];
			}
				for (int p = 0; p < i; p++)
				{
					memset(in_sign, false, sizeof(in_sign));
					if (incantation[p].head == 'b')
					{
						in_sign[p] = true;
						dfs(incantation[p].end);
					}
					if (can == true)
					{
						
						break;
					}
				}
				if(can==false)
				{
					printf("No.\n");
				}
				else printf("Yes.\n");
			}
			return 0;
		}