Compilare: user.cpp: In function ‘int main()’: user.cpp:47:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0; i<muchii[x].size(); i++) ~^~~~~~~~~~~~~~~~~ user.cpp:51:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(j=0; j<muchii[x].size(); j++) ~^~~~~~~~~~~~~~~~~ user.cpp:54:15: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0; i<muchii[x].size(); i++) ~^~~~~~~~~~~~~~~~~ user.cpp:36:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] { freopen("atac2.in", "r",stdin); ^ user.cpp:37:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("atac2.out", "w",stdout); ^ user.cpp:39:38: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d%d", &n, &m, &u, &x); ^ user.cpp:41:33: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &unitati[i]); ^ user.cpp:43:31: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &x1, &y); ^