#include //#include //#pragma GCC optimize("Ofast") using namespace std; #define reps(i,s,n) for(int i = s; i < n; i++) #define rep(i,n) reps(i,0,n) #define Rreps(i,n,e) for(int i = n - 1; i >= e; --i) #define Rrep(i,n) Rreps(i,n,0) #define ALL(a) a.begin(), a.end() #define fi first #define se second typedef long long ll; typedef vector vec; typedef vector mat; ll N,M,H,W,Q,K,A,B; string S; typedef pair P; const ll INF = (1LL<<60); int main() { cin>>S; rep(i, 26){ if(S[i] - 'a' != i){ cout<