Compilare: main.cpp: In function 'int main()': main.cpp:53:40: warning: format '%d' expects argument of type 'int', but argument 4 has type 'std::vector<int>::size_type {aka long unsigned int}' [-Wformat=] fprintf(out, "%d %d\n", ans, s.size()); ^ main.cpp:29:25: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf(in, "%d\n", &n); ^ main.cpp:33:34: warning: ignoring return value of 'int fscanf(FILE*, const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] fscanf(in, "%d %d\n", &x, &y); ^