case 7 is indeed right.
"fscanf("%d %d\n") and fgets" is INCORRECT.
not due to the bug of test case, but due to your wrong algorithm!


but, case 17 and 18 must be wrong.
    for (;;)
    {
        char ch=fgetc(Fin);
        if (ch=='\n') break;
        ...
    }
these codes will TLE on 17. there mustn't be '\n' in case 17.


for case 18, my C++ program is nearlly the same as my teammates' pascal program, but my fails on 18, his one gets AC.