delete pics to save space

1.4171.cpp

@@ -0,0 +1,69 @@
+#include<cstdio>
+#include<cstring>
+#include<vector>
+#include<algorithm>
+using namespace std;
+const int maxn=205;
+struct TwoSAT
+{
+	int n,stk[maxn*2],mark[maxn*2],c;
+	vector<int> G[maxn*2];
+	void init(int nn)
+	{
+		n=nn;
+		for(int i=0;i<n*2;i++) G[i].clear();
+		memset(mark,0,sizeof(mark));
+	}
+	void Add(int x,int xval,int y,int yval)
+	{
+//		printf("a[%d] equals to %d  or  a[%d] equals to %d\n",x,xval,y,yval);
+		x=x*2+xval; y=y*2+yval;
+		G[x^1].push_back(y);
+		G[y^1].push_back(x);
+	}
+	bool dfs(int u)
+	{
+		if(mark[u^1]) return false;
+		if(mark[u]) return true;
+		mark[u]=1;
+		stk[c++]=u;
+		for(int v:G[u]) if(!dfs(v)) return false;
+		return true;
+	}
+	bool solve()
+	{
+		for(int i=0;i<n*2;i+=2) if(!mark[i]&&!mark[i+1])
+		{
+			c=0;
+			if(!dfs(i))
+			{
+				while(c>0) mark[stk[--c]]=0;
+				if(!dfs(i+1)) return false;
+			}
+		}
+		return true;
+	}
+}alg;
+int T,n,m,hsh[128];
+int main()
+{
+#ifdef local
+	freopen("pro.in","r",stdin);
+#endif
+	scanf("%d",&T);
+	hsh['m']=0; hsh['h']=1;
+	while(T-->0)
+	{
+		scanf("%d%d",&n,&m);
+		alg.init(n);
+		while(m-->0)
+		{
+			char a[10],b[10]; scanf("%s%s",a,b);
+			int x,y; sscanf(a+1,"%d",&x); sscanf(b+1,"%d",&y);
+			x--; y--;
+			alg.Add(x,hsh[a[0]],y,hsh[b[0]]);
+		}
+		puts(alg.solve()?"GOOD":"BAD");
+	}
+	return 0;
+}