1029 旧键盘 (20分)
https://pintia.cn/problem-sets/994805260223102976/problems/994805292322111488
#include <iostream>
#include <cctype>
using namespace std;
int main()
{
string str1,str2,ans;
cin>>str1>>str2;
for(int i=0;i<str1.length();i++)
if((str2.find(str1[i])==string::npos)&&ans.find(toupper(str1[i]))==string::npos)
ans+=toupper(str1[i]);
cout<<ans<<endl;
return 0;
}
原文：https://www.cnblogs.com/jianqiao123/p/12246863.html