Compilare: main.cpp: In function 'int main()': main.cpp:69:24: warning: unused variable 'val' [-Wunused-variable] int t, c, i, n, k, val, x, a, b, s; ^~~ main.cpp: In member function 'char InParser::read_ch()': main.cpp:17:38: warning: ignoring return value of 'size_t fread(void*, size_t, size_t, FILE*)', declared with attribute warn_unused_result [-Wunused-result] fread(buff, 1, 4096, fin); ^