Compilare: user.cpp: In function ‘int main()’: user.cpp:15:24: warning: unused variable ‘j’ [-Wunused-variable] int n, x, y, z, i, j; ^ user.cpp:19:42: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fi,"%d%d%d%d", &n, &x, &y, &z); ^ user.cpp:21:31: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fi,"%d", &v[i]); ^