Compilare: user.cpp: In function ‘int main()’: user.cpp:148:40: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("rangemode.in", "r", stdin); ^ user.cpp:149:42: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("rangemode.out", "w", stdout); ^ user.cpp: In function ‘char getChar()’: user.cpp:16:38: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fread( buffer, BS, 1, stdin ); ^ user.cpp: In function ‘int queryHeap()’: user.cpp:98:12: warning: ‘value’ may be used uninitialized in this function [-Wmaybe-uninitialized] return value; ^