island.cpp:17:18: warning: use of 'auto' in parameter declaration only available with '-fconcepts-ts'
17 | auto &operator<<(auto &o, pair<auto, auto> p) {
| ^~~~
island.cpp:17:32: warning: use of 'auto' in parameter declaration only available with '-fconcepts-ts'
17 | auto &operator<<(auto &o, pair<auto, auto> p) {
| ^~~~
island.cpp:17:38: warning: use of 'auto' in parameter declaration only available with '-fconcepts-ts'
17 | auto &operator<<(auto &o, pair<auto, auto> p) {
| ^~~~
island.cpp:19:17: warning: use of 'auto' in parameter declaration only available with '-fconcepts-ts'
19 | auto operator<<(auto &o, auto x)->decltype(end(x), o) {
| ^~~~
island.cpp:19:26: warning: use of 'auto' in parameter declaration only available with '-fconcepts-ts'
19 | auto operator<<(auto &o, auto x)->decltype(end(x), o) {
| ^~~~
island.cpp: In function 'void solve(int, int)':
island.cpp:48:28: warning: comparison of integer expressions of different signedness: 'std::vector<int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
48 | while(edg[v].size()<n-1){
| ~~~~~~~~~~~~~^~~~