
1 #include <cstdio> 2 #include <cstring> 3 #include <string> 4 #include <string.h> 5 #include <cmath> 6 #include <iostream> 7 #include <algorithm> 8 #include <queue> 9 #include <stack> 10 #include <vector> 11 typedef long long ll; 12 using namespace std; 13 bool mp[311][311]; 14 int main() { 15 string s; 16 cin>>s; 17 int x=200,y=200; 18 for(int i=0;i<s.size();++i) 19 { 20 mp[x][y]=1; 21 if(s[i]=='L') x--; 22 if(s[i]=='R') x++; 23 if(s[i]=='U') y++; 24 if(s[i]=='D') y--; 25 if(mp[x][y]+mp[x-1][y]+mp[x+1][y]+mp[x][y-1]+mp[x][y+1]>1) 26 { 27 cout<<"BUG"<<endl; 28 return 0; 29 } 30 } 31 cout<<"OK"<<endl; 32 return 0; 33 }