Eroare de compilare: user.cpp: In function ‘int main()’: user.cpp:14:21: error: ‘l’ was not declared in this scope if (x == 0) if (v[l] == a) fout << upper_bound(v + 1, v + n + 1, a) - v - 1;; ^ user.cpp:15:4: error: ‘else’ without a previous ‘if’ else fout << -1; ^ user.cpp:20:17: warning: ignoring return value of ‘int system(const char*)’, declared with attribute warn_unused_result [-Wunused-result] system("pause"); ^