Compilare: user.cpp: In function ‘void update()’: user.cpp:51:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0;i < E.size(); i++) ^ user.cpp: In function ‘void solve(int)’: user.cpp:66:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < a[x].size(); i++) ^ user.cpp: In function ‘int main()’: user.cpp:78:33: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d%d%d",&xx,&m,&k); ^ user.cpp:85:48: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d%d%d%d",&type, &id, &x, &y); ^ user.cpp:103:26: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d",&x); ^