transfer.cpp: In function 'std::vector<int> get_attachment(std::vector<int>)':
transfer.cpp:5:2: error: 'n' was not declared in this scope
5 | n=v.size();
| ^
transfer.cpp: In function 'std::vector<int> retrieve(std::vector<int>)':
transfer.cpp:19:10: error: 'n' was not declared in this scope; did you mean 'nn'?
19 | int nn=(n>100?9:7);
| ^
| nn
transfer.cpp:22:24: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
22 | for(int i=v.size()-1;i>=v.size()-nn;i--)g^=v[i];
| ~^~~~~~~~~~~~~