Compilare: user.cpp: In function ‘int main()’: user.cpp:23:22: warning: operation on ‘k’ may be undefined [-Wsequence-point] l[++k] = r[k] = x; ^ user.cpp:25:20: warning: suggest parentheses around ‘&&’ within ‘||’ [-Wparentheses] while ((k > 1) && (l[k] == r[k - 1] + 1) || (l[k - 1] == r[k] + 1)) { ^ user.cpp:19:22: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f, "%d", &n); ^ user.cpp:22:24: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f, "%d", &x); ^