Compilare: user.cpp: In function ‘void makefor(int)’: user.cpp:17:20: warning: array subscript has type ‘char’ [-Wchar-subscripts] if (v[t][str[i]]) nod[i] = v[t][str[i]]; ^ user.cpp:17:43: warning: array subscript has type ‘char’ [-Wchar-subscripts] if (v[t][str[i]]) nod[i] = v[t][str[i]]; ^ user.cpp:18:21: warning: array subscript has type ‘char’ [-Wchar-subscripts] else v[t][str[i]] = nod[i] = ++k; ^ user.cpp: In function ‘int main()’: user.cpp:24:48: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("aiacupalindroame.in", "r", stdin); ^ user.cpp:25:50: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("aiacupalindroame.out", "w", stdout); ^ user.cpp:28:28: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d %d", &n, &q); ^ user.cpp:31:28: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d", &a[i]); ^ user.cpp:33:17: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("\n"); ^ user.cpp:34:19: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets (str + 2); ^ user.cpp:46:32: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d %d", &x, &y); ^ /tmp/cc1PnH7g.o: In function `main': user.cpp:(.text.startup+0xb0): warning: the `gets' function is dangerous and should not be used.