Compilare: user.cpp: In function ‘void clearintrv()’: user.cpp:49:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < intrv.size(); i++) ^ user.cpp: In function ‘void qry(int)’: user.cpp:65:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < intrv.size(); i++) ^ user.cpp: In function ‘void rev(int, int)’: user.cpp:90:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < intrv.size(); i++) ^ user.cpp:118:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < intrv.size(); i++) ^ user.cpp: In function ‘char gchar()’: user.cpp:18:38: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread(buff, buffer, 1, stdin); ^ user.cpp: In function ‘int main()’: user.cpp:154:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("rev.in", "r", stdin); ^ user.cpp:155:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("rev.out", "w", stdout); ^