train.cpp: In function 'vi operator-(vi, vi)':
train.cpp:22:23: 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 = 0; i < a.size(); i++){
| ~~^~~~~~~~~~
train.cpp:23:17: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
23 | while(j < b.size() && b[j] < a[i])
| ~~^~~~~~~~~~
train.cpp:26:15: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
26 | if (j == b.size() || b[j] > a[i])
| ~~^~~~~~~~~~~
train.cpp: In function 'vi f(bool, vi)':
train.cpp:38:25: warning: suggest parentheses around assignment used as truth value [-Wparentheses]
38 | vis[i] = deg[i] = 0;
| ~~~~~~~^~~
train.cpp:43:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
43 | for (int j = 0; j < adjList[i].size(); j++){
| ~~^~~~~~~~~~~~~~~~~~~
train.cpp:51:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
51 | for (int i = 0; i < x.size(); i++)
| ~~^~~~~~~~~~
train.cpp:57:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
57 | for (int i = 0; i < adjList[curr].size(); i++){
| ~~^~~~~~~~~~~~~~~~~~~~~~
train.cpp: In function 'vi who_wins(vi, vi, vi, vi)':
train.cpp:91:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
91 | for (int i = 0; i < graph.size(); i++)
| ~~^~~~~~~~~~~~~~
train.cpp:100:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
100 | for (int i = 0; i < f_b.size(); i++)
| ~~^~~~~~~~~~~~
train.cpp:107:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
107 | for (int i = 0; i < graph.size(); i++)
| ~~^~~~~~~~~~~~~~