Compilare: user.cpp: In function ‘int find(int)’: user.cpp:23:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j=0; j<H[i].size(); j++) ^ user.cpp: In function ‘void read()’: user.cpp:15:32: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d", &N, &L, &U); ^ user.cpp:16:47: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] for(int i=1; i<=N; i++) scanf("%d", &A[i]); ^ user.cpp: In function ‘int main()’: user.cpp:51:24: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen(inf,"r",stdin); freopen(outf,"w",stdout); ^ user.cpp:51:50: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen(inf,"r",stdin); freopen(outf,"w",stdout); ^