Submission #1187901

#	Time	Username	Problem	Language	Result	Execution time	Memory
1187901		versesrev	Tracks in the Snow (BOI13_tracks)	C++20	Compilation error	0 ms	0 KiB

tracks

#include <iostream>
#include <vector>
#include <string>
#include <deque>
#include <tuple>

int main() {
  int h, w;
  std::cin >> h >> w;
  std::vector<std::string> grid(h);
  for (auto& s : grid) std::cin >> s;
  
  int ans = 0;
  int dr[4] = {1, 0, -1, 0};
  int dc[4] = {0, 1, 0, -1};
  std::deque<std::tuple<int, int, int>> que[2];
  std::vector<std::vector<bool>> vis(h, std::vector<bool>(w));
  int cur = 0;
  que[cur].emplace(0, 0, 0), vis[0][0] = true;
  while (not que[cur].empty() or not que[cur^1].empty()) {
    if (que[cur].empty()) cur ^= 1;
    auto [d, r, c] = que[cur].top();
    que[cur].pop();
    for (int k = 0; k < 4; ++k) {
      int nr = r + dr[k];
      int nc = c + dc[k];
      if (nr < 0 or h <= nr
      or nc < 0 or w <= nc
      or vis[nr][nc]
      or '.' == grid[nr][nc]) continue;
      int nd = d - (grid[nr][nc] != grid[r][c]);
      que[cur^1].emplace(nd, nr, nc);
      vis[nr][nc] = true;
      ans = std::max(ans, -d);
    }
  }
  std::cout << (ans + 1) << "\n";
}

Compilation message (stderr)

tracks.cpp: In function 'int main()':
tracks.cpp:19:19: error: no matching function for call to 'std::deque<std::tuple<int, int, int> >::emplace(int, int, int)'
   19 |   que[cur].emplace(0, 0, 0), vis[0][0] = true;
      |   ~~~~~~~~~~~~~~~~^~~~~~~~~
In file included from /usr/include/c++/11/deque:67,
                 from tracks.cpp:4:
/usr/include/c++/11/bits/stl_deque.h:1581:9: note: candidate: 'template<class ... _Args> std::deque<_Tp, _Alloc>::iterator std::deque<_Tp, _Alloc>::emplace(std::deque<_Tp, _Alloc>::const_iterator, _Args&& ...) [with _Args = {_Args ...}; _Tp = std::tuple<int, int, int>; _Alloc = std::allocator<std::tuple<int, int, int> >]'
 1581 |         emplace(const_iterator __position, _Args&&... __args);
      |         ^~~~~~~
/usr/include/c++/11/bits/stl_deque.h:1581:9: note:   template argument deduction/substitution failed:
tracks.cpp:19:20: note:   cannot convert '0' (type 'int') to type 'std::deque<std::tuple<int, int, int> >::const_iterator' {aka 'std::_Deque_base<std::tuple<int, int, int>, std::allocator<std::tuple<int, int, int> > >::const_iterator'}
   19 |   que[cur].emplace(0, 0, 0), vis[0][0] = true;
      |                    ^
tracks.cpp:22:31: error: 'class std::deque<std::tuple<int, int, int> >' has no member named 'top'
   22 |     auto [d, r, c] = que[cur].top();
      |                               ^~~
tracks.cpp:23:14: error: 'class std::deque<std::tuple<int, int, int> >' has no member named 'pop'
   23 |     que[cur].pop();
      |              ^~~
tracks.cpp:32:25: error: no matching function for call to 'std::deque<std::tuple<int, int, int> >::emplace(int&, int&, int&)'
   32 |       que[cur^1].emplace(nd, nr, nc);
      |       ~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~
In file included from /usr/include/c++/11/deque:67,
                 from tracks.cpp:4:
/usr/include/c++/11/bits/stl_deque.h:1581:9: note: candidate: 'template<class ... _Args> std::deque<_Tp, _Alloc>::iterator std::deque<_Tp, _Alloc>::emplace(std::deque<_Tp, _Alloc>::const_iterator, _Args&& ...) [with _Args = {_Args ...}; _Tp = std::tuple<int, int, int>; _Alloc = std::allocator<std::tuple<int, int, int> >]'
 1581 |         emplace(const_iterator __position, _Args&&... __args);
      |         ^~~~~~~
/usr/include/c++/11/bits/stl_deque.h:1581:9: note:   template argument deduction/substitution failed:
tracks.cpp:32:26: note:   cannot convert 'nd' (type 'int') to type 'std::deque<std::tuple<int, int, int> >::const_iterator' {aka 'std::_Deque_base<std::tuple<int, int, int>, std::allocator<std::tuple<int, int, int> > >::const_iterator'}
   32 |       que[cur^1].emplace(nd, nr, nc);
      |                          ^~