answer.code: In member function ‘i64 Flow::flow(int, int)’:
answer.code:88:47: error: ‘numeric_limits’ is not a member of ‘std’
   88 |                         ans += dfs(s, t, std::numeric_limits<int>::max());
      |                                               ^~~~~~~~~~~~~~
answer.code:88:62: error: expected primary-expression before ‘int’
   88 |                         ans += dfs(s, t, std::numeric_limits<int>::max());
      |                                                              ^~~
answer.code: In function ‘void solve()’:
answer.code:141:5: error: ‘function’ was not declared in this scope
  141 |     function < int (int, int) > legal = [&] (int x, int y)
      |     ^~~~~~~~
answer.code:7:1: note: ‘std::function’ is defined in header ‘<functional>’; did you forget to ‘#include <functional>’?
    6 | #include <queue>
  +++ |+#include <functional>
    7 | using namespace std;
answer.code:141:29: error: expression list treated as compound expression in functional cast [-fpermissive]
  141 |     function < int (int, int) > legal = [&] (int x, int y)
      |                             ^
answer.code:141:16: error: expected primary-expression before ‘int’
  141 |     function < int (int, int) > legal = [&] (int x, int y)
      |                ^~~
answer.code:147:29: error: expression list treated as compound expression in functional cast [-fpermissive]
  147 |     function < int (int, int) > code = [&] (int x, int y)
      |                             ^
answer.code:147:16: error: expected primary-expression before ‘int’
  147 |     function < int (int, int) > code = [&] (int x, int y)
      |                ^~~
answer.code:151:20: error: expected primary-expression before ‘(’ token
  151 |     function < PII (int) > decode = [&] (int code)
      |                    ^
answer.code:151:21: error: expected primary-expression before ‘int’
  151 |     function < PII (int) > decode = [&] (int code)
      |                     ^~~
answer.code:151:28: error: ‘decode’ was not declared in this scope
  151 |     function < PII (int) > decode = [&] (int code)
      |                            ^~~~~~
answer.code:164:32: error: ‘code’ was not declared in this scope
  164 |                 g.addEdge(sta, code(i, j), 1);
      |                                ^~~~
answer.code:169:24: error: ‘legal’ was not declared in this scope
  169 |                     if(legal(x, y) && str[x][y] != '#')
      |                        ^~~~~
answer.code:174:27: error: ‘code’ was not declared in this scope
  174 |                 g.addEdge(code(i, j), ed, 1);
      |                           ^~~~
answer.code:183:14: warning: structured bindings only available with ‘-std=c++17’ or ‘-std=gnu++17’ [-Wc++17-extensions]
  183 |         auto [x, y] = decode(code);
      |              ^