Lista

input/code.cpp: In function 'int main()':
input/code.cpp:18:33: warning: converting to 'std::stringstream {aka std::__cxx11::basic_stringstream<char>}' from initializer list would use explicit constructor 'std::__cxx11::basic_stringstream<_CharT, _Traits, _Alloc>::basic_stringstream(std::ios_base::openmode) [with _CharT = char; _Traits = std::char_traits<char>; _Alloc = std::allocator<char>; std::ios_base::openmode = std::_Ios_Openmode]'
   std::stringstream tulokset = {};
                                 ^
input/code.cpp:18:33: note: in C++11 and above a default constructor can be explicit
input/code.cpp:32:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         if (rivi[j] != '0' + num % 10) {

#include <iostream>
#include <sstream>

uint32_t mypow(uint32_t n, uint32_t p) {
  uint32_t res = 1;
  while (p--)
    res *= n;
  return res;
}

int main() {
  std::ios::sync_with_stdio(false);
  std::cin.tie(nullptr);

  uint32_t n;
  std::cin >> n;
  uint32_t ed = 0;
  std::stringstream tulokset = {};
  for (uint32_t i = 0; i < n; ++i) {
    std::string rivi;
    std::cin >> rivi;
    uint32_t l = mypow(10, rivi.size() - 1);
    bool outdone = false;
    for (uint32_t tst = std::max(ed + 1, l); tst < 10 * l; ++tst) {
      uint32_t num = tst;
      bool done = true;
      for (uint32_t j = rivi.size() - 1; j < rivi.size(); --j) {
        if (rivi[j] == '?') {
          num /= 10;
          continue;
        }
        if (rivi[j] != '0' + num % 10) {
	  tst = num / 10 * mypow(10, rivi.size() - j) + (rivi[j] - '0') * mypow(10, rivi.size() - j - 1) - 1;
          done = false;
          break;
        }
        num /= 10;
      }
      if (done) {
        ed = tst;
        tulokset << tst << '\n';
        outdone = true;
        break;
      }
    }
    if (!outdone) {
      std::cout << "IMPOSSIBLE\n";
      return 0;
    }
  }
  std::cout << tulokset.str();
}

Test 1

Group: 1, 2, 3

Verdict: WRONG ANSWER

Test 2

Group: 2, 3

Verdict: WRONG ANSWER

Test 3

Group: 3

Verdict: WRONG ANSWER

Test 4

Group: 1, 2, 3

Verdict: ACCEPTED

Test 5

Group: 1, 2, 3

Verdict: ACCEPTED

Test 6

Group: 1, 2, 3

Verdict: WRONG ANSWER

Test 7

Group: 1, 2, 3

Verdict: WRONG ANSWER

Test 8

Group: 3

Verdict: ACCEPTED

Test 9

Group: 3

Verdict: WRONG ANSWER

Test 10

Group: 3

Verdict: WRONG ANSWER