Compilare: user.cpp: In function ‘void dfs(int, int)’: user.cpp:41:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0; i<g[x].size(); i++) ^ user.cpp: In function ‘int main()’: user.cpp:49:18: warning: unused variable ‘j’ [-Wunused-variable] int n, m, i, j, x, y; ^ user.cpp:50:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("hektor.in","r",stdin); ^ user.cpp:51:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("hektor.out","w",stdout); ^ user.cpp:52:36: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d%d",&n,&m,&xi,&xf); ^ user.cpp:53:46: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] for (i=1; i<=n; i++) scanf("%d",&cost[i]); ^ user.cpp:56:28: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&x,&y); ^