Compilare: main.cpp: In function 'void precalc()': main.cpp:77:21: warning: unused variable 'dr' [-Wunused-variable] int dr=(int)log2(min(n-i+1,m-j+1)); ^~ main.cpp:91:17: warning: unused variable 'sol' [-Wunused-variable] int sol=2e9; ^~~ main.cpp: In member function 'char InParser::read_ch()': main.cpp:14:29: 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); ^