Compilare: user.cpp: In function ‘int main()’: user.cpp:104:21: warning: variable ‘z’ set but not used [-Wunused-but-set-variable] int n, m, x, y, z, a; ^ user.cpp: In function ‘char nextch()’: user.cpp:26:58: warning: ignoring return value of ‘size_t fread(void*, size_t, size_t, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] if(pos==BUF_SIZE) fread(buf, BUF_SIZE, 1, fin), pos=0; ^