Compilare: user.cpp: In function ‘int main()’: user.cpp:54:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(k=0;k<dr[j].size();k++) ^ user.cpp:94:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=1;i<dr[k].size();i++) ^ user.cpp:39:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("cerc3.in","r",stdin); ^ user.cpp:40:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("cerc3.out","w",stdout); ^ user.cpp:41:19: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&n); ^ user.cpp:45:33: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d",&x,&y,&r); ^