strange_device.cpp: In function 'int32_t main()':
strange_device.cpp:16:10: error: 'gcd' was not declared in this scope
16 | p /= gcd(a, b+1);
| ^~~
strange_device.cpp:44:10: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
44 | auto [l, r] = ranges[0];
| ^
strange_device.cpp:45:23: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
45 | for (int i = 1; i < ranges.size(); ++i) {
| ~~^~~~~~~~~~~~~~~
strange_device.cpp:46:14: warning: structured bindings only available with '-std=c++17' or '-std=gnu++17'
46 | auto [lb, rb] = ranges[i];
| ^