Compilare: main.cpp: In function 'void dfs_build(int, int)': main.cpp:27:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<g[nod].size(); i++) ~^~~~~~~~~~~~~~ main.cpp: In function 'void solve(int)': main.cpp:55:19: 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:62:40: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] { freopen("spiridusi.in", "r", stdin); ^ main.cpp:63:42: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("spiridusi.out", "w", stdout); ^ main.cpp:65:26: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &n, &c); ^ main.cpp:67:30: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &cost[i]); ^ main.cpp:69:30: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &prof[i]); ^ main.cpp:71:30: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &x, &y); ^