foo.cc:19:5: warning: multi-line comment [-Wcomment]
   19 |     // do {                        \
      |     ^
foo.cc: In lambda function:
foo.cc:49:26: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   49 |                     auto [v, i] = *it;
      |                          ^
foo.cc:61:26: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   61 |                     auto [v, i] = *it;
      |                          ^
foo.cc: In function 'void solve()':
foo.cc:75:15: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
   75 |     for(auto &[par,it] : mp) {
      |               ^

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