模拟即可。样例已经涵盖了所有注意事项。

#include <bits/stdc++.h>
using namespace std;
string check(string answer, string output)
{
    if (answer == output) return "Accepted.";
    int line = 1, column = 1, al = answer.size(), ol = output.size();
    stringstream conv;
    string res;
    conv << "Wrong Answer: ";
    for (int i = 0; i < min (al, ol); i++)
    {
        if (answer[i] != output[i])
        {
            if (answer[i] == '\n') conv << "Extra Character";
            else if (output[i] == '\n') conv << "Missing Character";
            else conv << "Wrong Answer";
            conv << " on Line " << line << ", Column " << column << ".";
            getline(conv, res);
            return res;
        }
        if (answer[i] == '\n') line++, column = 1;
        else column++;
    }
    if (al > ol)
    {
        if (answer[ol] == '\n') conv << "Missing Line on Line " << line + 1 <<".";
        else conv << "Missing Character on Line " << line << ", Column " << column << ".";
    }
    else
    {
        if (output[al] == '\n') conv << "Extra Line on Line " << line + 1 <<".";
        else conv << "Extra Character on Line " << line << ", Column " << column << ".";
    }
    getline(conv, res);
    return res;
}
int main()
{
    freopen("check.in", "r", stdin);
    freopen("check.out", "w", stdout);
    string ansa, out;
    stringstream s0, s1, s2;
    bool sepa = false;
    char c = getchar();
    while (c != EOF)
    {
        s0 << (int) c << endl;
        if (c == 127) sepa = true;
        else if (sepa) s2 << '*';
        else s1 << '*';
        c = getchar();
    }
    s1 >> ansa;
    s2 >> out;
    int tmp = 0, cnt = 0;
    sepa = false;
    while (s0 >> tmp)
    {
        if (tmp == 127)
        {
            sepa = true;
            cnt = 0;
        }
        else
        {
            if (sepa) out[cnt] = tmp;
            else ansa[cnt] = tmp;
            cnt++;
        }
    }
    cout << check(ansa, out);
    return 0;
}