#include using namespace std; //#include //using namespace atcoder; using ll=long long; using Graph=vector>; #define MOD 998244353 #define INF 1000000000000000000 #define MAX 2000 int main(){ string S; cin>>S; char c; if(S[0]==S[1]){ c=S[0]; }else if(S[1]==S[2]){ c=S[1]; }else{ S[0]; } int i=0; while(S[i]==c){ i++; } cout<