题解 | #字符串合并处理#

输入输出流和bitset来做

#include<bits/stdc++.h>
//#include <cctype>
using namespace std;
map<char,char>t = {{1,2},{}};
int main(){
    string s1,s2;
    cin>>s1>>s2;
    string s = s1+s2;
    s1="";s2="";
    for(int i = 0; 2*i < s.size();i++){
        s1+=(s[2*i]);
        if(2*i+1<s.size())
        s2+=(s[2*i+1]);
    }
    sort(s1.begin(),s1.end());
    sort(s2.begin(), s2.end());
    for(int i = 0; 2*i < s.size();i++){
        s[2*i] = s1[i];
        if(2*i+1<s.size())
        s[2*i+1] = s2[i];
    }
    string res ="";
    for(auto c: s){
        if((c>='0'&&c<='9') || (c>='a' &&c<='f') || (c>='A' &&c<='F'))
        {
            bitset<4> bits(stoi(string (1,c), nullptr, 16));
            string tmp = bits.to_string();
            reverse(tmp.begin(),tmp.end());
            stringstream  ss;
            string hex;
            ss<<hex<<std::hex<<stoi(tmp, nullptr, 2);
            ss>>hex;
            transform(hex.begin(), hex.end(),hex.begin(),::toupper);
            res+=hex;
        }
        else
        res+=c;
    }
    cout<<res<<endl;
}