train.cpp: In function 'bool dfs(int, int, int)':
train.cpp:14:17: warning: statement has no effect [-Wunused-value]
14 | #define DE(...) 0
| ^
train.cpp:36:2: note: in expansion of macro 'DE'
36 | DE(x, s, v);
| ^~
train.cpp:14:17: warning: statement has no effect [-Wunused-value]
14 | #define DE(...) 0
| ^
train.cpp:54:3: note: in expansion of macro 'DE'
54 | DE(x, dp[x]);
| ^~
train.cpp:14:17: warning: statement has no effect [-Wunused-value]
14 | #define DE(...) 0
| ^
train.cpp:71:5: note: in expansion of macro 'DE'
71 | DE(u, 0);
| ^~
train.cpp:14:17: warning: statement has no effect [-Wunused-value]
14 | #define DE(...) 0
| ^
train.cpp:76:3: note: in expansion of macro 'DE'
76 | DE(x, dp[x]);
| ^~
train.cpp: In function 'std::vector<int> who_wins(std::vector<int>, std::vector<int>, std::vector<int>, std::vector<int>)':
train.cpp:14:17: warning: statement has no effect [-Wunused-value]
14 | #define DE(...) 0
| ^
train.cpp:94:3: note: in expansion of macro 'DE'
94 | DE(i, w[i], belong[i]);
| ^~
train.cpp:96:19: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
96 | for (int i = 0;i < u.size();++i) {
| ~~^~~~~~~~~~
train.cpp:14:17: warning: statement has no effect [-Wunused-value]
14 | #define DE(...) 0
| ^
train.cpp:98:3: note: in expansion of macro 'DE'
98 | DE(u[i], v[i]);
| ^~
train.cpp:14:17: warning: statement has no effect [-Wunused-value]
14 | #define DE(...) 0
| ^
train.cpp:104:3: note: in expansion of macro 'DE'
104 | DE(i);
| ^~