Compilare: main.cpp: In function 'int main()': main.cpp:134:21: warning: unused variable 'ending' [-Wunused-variable] int ending = aux -> second; ^~~~~~ main.cpp:84:9: warning: unused variable 'i' [-Wunused-variable] int i,j; ^ main.cpp:84:11: warning: unused variable 'j' [-Wunused-variable] int i,j; ^ main.cpp:87:36: 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 , 4000000 , fin); ^