#include<iostream>
#include<string>
#include<map>
using namespace std;
int main()
{
string str;
while(getline(cin,str))
{
map<char,int>res;
for(int i=0;i<str.size();i++)
{
res[str[i]]++;
}
for(int i=0;i<str.size();i++)
{
if(res[str[i]]==1)
{
cout<<str[i]<<endl;
break;
}
//如果到最後一個元素還沒有找到跳出,則輸出“-1”
if(i==str.size()-1)
cout<<"-1"<<endl;
}
}
}
劍指offer類似題:
https://blog.csdn.net/SHAOYEZUIZUISHAUI/article/details/105731894
https://blog.csdn.net/SHAOYEZUIZUISHAUI/article/details/105721006