transfer.cpp: In function 'std::vector<int> get_attachment(std::vector<int>)':
transfer.cpp:12:11: error: 'N' was not declared in this scope
12 | int n = N;
| ^
transfer.cpp: In function 'std::vector<int> retrieve(std::vector<int>)':
transfer.cpp:40:15: error: 'N' was not declared in this scope
40 | for(int i = N; i < datasize - 1; i++){
| ^
transfer.cpp:46:22: error: 'N' was not declared in this scope
46 | for(int i = 0; i < N; i++) ret.push_back(data[i]);
| ^
transfer.cpp:51:22: error: 'N' was not declared in this scope
51 | for(int i = 0; i < N; i++){
| ^