UVa Self-Assembly(topo sort)[待AC]

#include<iostream>
#include<cstring>
#include<cstdio>
#include<cctype>
using namespace std;
int G[52][52],c[52];
bool topo(int u)
{
//	printf("%c ",u%26+'A');
c[u]=-1;   //visiting;
for(int v=0;v<52;v++)
{

if(G[u][v]){
//			printf("%c %c\n",u%26+'A',v%26+'A');
int p=v<26?v+26:v-26;
if(c[p]<0) return true;
else if(!c[p]&&topo(p)) return true;
}
}
c[u]=1;
return false;
}
void print()
{
for(int i=0;i<52;i++)
cout<<c[i]<<' ';
cout<<endl;
}
bool check()
{

for(int u=0;u<52;u++)
{
if(!c[u])
{
//			cout<<u<<endl;
if(topo(u)) {
return true;
}
//			print();
}
}

return false;
}
int main()
{
int n;
while(scanf("%d",&n)==1&&n)
{
char s[10];
memset(G,0,sizeof(G));
memset(c,0,sizeof(c));
for(int i=0;i<n;i++)
{
scanf("%s",s);
int letter[3]={0},sign[3]={0},p=0;
for(int i=0;i<8;i+=2)
{
if(isdigit(s[i])) continue;
letter[p]=s[i]-'A';
sign[p]=s[i+1]=='+'?0:26;
p++;
}
for(int i=0;i<3;i++)
{
int l=letter[i]+sign[i];
//				c[l]=-1;   //existed
for(int j=1;j<=2;j++)
{
int m=letter[(i+j)%3]+sign[(i+j)%3];
G[l][m]=1;
//				printf("%c %c\n",m%26+'A',l%26+'A');
}
}
}
if(check())	printf("un");
printf("bounded\n");
}
return 0;
}