Compilare: user.cpp: In function ‘int main()’: user.cpp:51:12: warning: unused variable ‘i’ [-Wunused-variable] int n, i, j; ^ user.cpp:51:15: warning: unused variable ‘j’ [-Wunused-variable] int n, i, j; ^ user.cpp:52:31: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(in, "%d%d", &n, &k); ^ user.cpp:55:32: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(in, "%d", &v[i]); ^