Compilare: user.cpp: In function ‘long long int solveHist(int)’: user.cpp:55:105: warning: operation on ‘stackSize’ may be undefined [-Wsequence-point] maxArea = MAX(maxArea, 1LL * hist[st[--stackSize]] * (!stackSize ? i : i - 1 - st[stackSize - 1])); ^ user.cpp: In function ‘char getChar(FILE*)’: user.cpp:23:34: 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, BUFFSIZE, f); ^