Compilare: main.cpp: In function 'void dfs(int)': main.cpp:20:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<g[nod].size(); i++){ ~^~~~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:52:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j=0; j<sol[i].size(); j++) ~^~~~~~~~~~~~~~ main.cpp:39:34: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] { freopen("ctc.in", "r", stdin); ^ main.cpp:40:36: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("ctc.out", "w", stdout); ^ main.cpp:42:26: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &n, &m); ^ main.cpp:44:30: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &x, &y); ^