Compilare: user.cpp: In function ‘void dfs(int)’: user.cpp:22:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i = 0; i < v[x].size(); i++) { ^ user.cpp: In function ‘void graf(int)’: user.cpp:39:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j=0;j<v[x].size();j++) ^ user.cpp:33:9: warning: unused variable ‘i’ [-Wunused-variable] int i,j,y; ^ user.cpp: In function ‘int main()’: user.cpp:66:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("easygraph.in","r",stdin); ^ user.cpp:67:41: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("easygraph.out","w",stdout); ^ user.cpp:68:19: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&t); ^ user.cpp:72:28: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&n,&m); ^ user.cpp:76:33: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&cost[i]); ^ user.cpp:82:29: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d",&x,&y); ^