Compilare: user.c: In function ‘main’: user.c:128:8: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("trie.in", "r", stdin); ^ user.c:129:8: warning: ignoring return value of ‘freopen’, declared with attribute warn_unused_result [-Wunused-result] freopen("trie.out", "w", stdout); ^ user.c:138:14: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &task); ^ user.c:140:10: warning: ignoring return value of ‘scanf’, declared with attribute warn_unused_result [-Wunused-result] scanf("%s", word); ^ user.c: In function ‘LongestPrefix’: user.c:63:21: warning: ‘index’ may be used uninitialized in this function [-Wmaybe-uninitialized] }if((ptr -> edge[index]) -> occurences) prefix = i+1; ^