Compilare: user.cpp: In function ‘int main()’: user.cpp:57:12: warning: variable ‘m’ set but not used [-Wunused-but-set-variable] int n, m, i, k, x, y, p, q, t, r; ^ user.cpp:57:36: warning: unused variable ‘r’ [-Wunused-variable] int n, m, i, k, x, y, p, q, t, r; ^ user.cpp:58:10: warning: unused variable ‘ch’ [-Wunused-variable] char ch; ^ user.cpp:59:15: warning: unused variable ‘ans’ [-Wunused-variable] long long ans; ^ user.cpp: In function ‘char nextch()’: user.cpp:13:58: 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; ^