#include <bits/stdc++.h> using namespace std; int main(){ char s[100005]; cin>>s; for(int i=0;i<strlen(s);i++){ int flag=0; for(int j=0;j<strlen(s);j++){ if(s[j]s[i] && i!=j) flag=1; } if(flag0){ cout<<s[i]; return 0; } } cout<<"no"; return 0; }

e = input() de = {} for i in e: if i not in de: de[i] = 1 else: de[i]+=1 for i in de: if de[i] == 1: print(i) break else: print("no")

python: a = input() for i in a: if a.count(i) == 1: print(i) break else: print('no')