Compilare: user.cpp: In function ‘int main()’: user.cpp:8:12: warning: unused variable ‘b’ [-Wunused-variable] int a, b, n, x, sum, i, k, j; ^ user.cpp:8:18: warning: unused variable ‘x’ [-Wunused-variable] int a, b, n, x, sum, i, k, j; ^ user.cpp:8:32: warning: unused variable ‘j’ [-Wunused-variable] int a, b, n, x, sum, i, k, j; ^ user.cpp:12:21: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin,"%d", &n); ^ user.cpp:14:24: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin,"%d", &v[i]); ^