doll.cpp: In function 'int build(std::vector<int>)':
doll.cpp:17:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
17 | for(int i = 0; i < cur.size(); i+=2) {
| ~~^~~~~~~~~~~~
doll.cpp:23:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
23 | for(int i = 1; i < cur.size(); i+=2) {
| ~~^~~~~~~~~~~~
doll.cpp: In function 'void create_circuit(int, std::vector<int>)':
doll.cpp:46:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
46 | for(int i = 0; i < A.size(); i++) {
| ~~^~~~~~~~~~
doll.cpp:32:7: warning: unused variable 'N' [-Wunused-variable]
32 | int N = A.size();
| ^