题解 | #字符串合并处理#

#include<bits/stdc++.h>
using namespace std;
int main()
{
    string str1, str2, ans;
    while (cin >> str1 >> str2)
    {
        char Out[] = {"084C2A6E195D3B7F5D3B7F"};//0123456789abcdefABCDEF
        ans = str1 + str2;
        string odd,even;
        for (int i = 0; i < ans.size(); i++)
            if (i % 2 == 0)
                odd += ans[i];
            else if (i % 2 == 1)
                even += ans[i];
        sort(odd.begin(), odd.end());
        sort(even.begin(), even.end());
        int j = 0, k = 0;
        for (int i = 0; i < ans.size(); i++)
            if (i % 2 == 0)
                ans[i] = odd[j++];
            else if (i % 2 == 1)
                ans[i] = even[k++];
        for (int i = 0; i < ans.size(); i++)
            if (isdigit(ans[i]))
                ans[i] = Out[ans[i] - '0'];
            else if (ans[i] >= 'a' && ans[i] <= 'f')
                ans[i] = Out[ans[i] - 'a' + 10];
            else if (ans[i] >= 'A' && ans[i] <= 'F')
                ans[i] = Out[ans[i] - 'A' + 16];
        cout << ans << endl;
    }
}