Compilare: main.cpp: In function 'int main()': main.cpp:81:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0; i<ap[u].size(); i++) ~^~~~~~~~~~~~~ main.cpp:30:39: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] { freopen("showroom.in", "r", stdin); ^ main.cpp:31:40: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("showroom.out", "w",stdout); ^ main.cpp:34:40: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d%d\n", &n, &a, &r, &k); ^