train.cpp: In function 'bool haveCycle(int, int)':
train.cpp:18:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
18 | for(int i = 0; i < ar[cur].size(); i++){
| ~~^~~~~~~~~~~~~~~~
train.cpp: In function 'void dfs(int)':
train.cpp:30:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
30 | for(int i = 0; i < rev[cur].size(); i++){
| ~~^~~~~~~~~~~~~~~~~
train.cpp: In function 'std::vector<int> sub3(std::vector<int>, std::vector<int>)':
train.cpp:64:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
64 | for(int i = 0; i < r.size(); i++){
| ~~^~~~~~~~~~
train.cpp:66:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
66 | for(int j = 0; j < r.size(); j++)
| ~~^~~~~~~~~~
train.cpp: In function 'std::vector<int> sub4(std::vector<int>, std::vector<int>)':
train.cpp:81:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
81 | for(int j = 0; j < r.size(); j++)
| ~~^~~~~~~~~~
train.cpp: In function 'std::vector<int> who_wins(std::vector<int>, std::vector<int>, std::vector<int>, std::vector<int>)':
train.cpp:106:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
106 | for(int i = 0; i < u.size(); i++){
| ~~^~~~~~~~~~