Compilare: user.cpp: In function ‘int query(int, int, int, int, int)’: user.cpp:132:63: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while (f1 < 0 || (f1 >= 0 && f1 < aint [node].v.size () && aint [node].v [f1].y < yy1 )) ^ user.cpp:127:21: warning: unused variable ‘numst’ [-Wunused-variable] int m, ans = 0, numst = 0, nf1, nf2; ^ user.cpp: In member function ‘void Myifstream::advance()’: user.cpp:46:47: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread (buffer, 1, SIZE, input); ^ user.cpp: In constructor ‘Myifstream::Myifstream(const char*)’: user.cpp:53:43: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread (buffer, 1, SIZE, input); ^ user.cpp: In member function ‘Myifstream& Myifstream::operator>>(int&)’: user.cpp:63:13: warning: ‘semn’ may be used uninitialized in this function [-Wmaybe-uninitialized] if (semn == '-') ^ user.cpp: In function ‘int main()’: user.cpp:63:13: warning: ‘semn’ may be used uninitialized in this function [-Wmaybe-uninitialized] user.cpp:57:18: note: ‘semn’ was declared here char semn; ^ user.cpp:63:13: warning: ‘semn’ may be used uninitialized in this function [-Wmaybe-uninitialized] if (semn == '-') ^ user.cpp:57:18: note: ‘semn’ was declared here char semn; ^ user.cpp:63:13: warning: ‘semn’ may be used uninitialized in this function [-Wmaybe-uninitialized] if (semn == '-') ^ user.cpp:57:18: note: ‘semn’ was declared here char semn; ^ user.cpp:63:13: warning: ‘semn’ may be used uninitialized in this function [-Wmaybe-uninitialized] if (semn == '-') ^ user.cpp:57:18: note: ‘semn’ was declared here char semn; ^ user.cpp:206:38: warning: ‘f2’ may be used uninitialized in this function [-Wmaybe-uninitialized] ans = query (1, 1, n, f1, f2); ^ user.cpp:206:38: warning: ‘f1’ may be used uninitialized in this function [-Wmaybe-uninitialized] user.cpp:63:13: warning: ‘semn’ may be used uninitialized in this function [-Wmaybe-uninitialized] if (semn == '-') ^ user.cpp:57:18: note: ‘semn’ was declared here