Compilare: main.cpp: In function 'int main()': main.cpp:121:42: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0, last=-2000000005, cnt=-1; i<arr.size(); i++){ ~^~~~~~~~~~~ main.cpp:135:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0;i < arr.size(); i++){ ~~^~~~~~~~~~~~ main.cpp: In member function 'char InParser::read_ch()': main.cpp:17:29: warning: ignoring return value of 'size_t fread(void*, size_t, size_t, FILE*)', declared with attribute warn_unused_result [-Wunused-result] fread(buff, 1, 4096, fin); ^