Compilare: user.cpp: In function ‘int main()’: user.cpp:22:19: warning: array subscript has type ‘char’ [-Wchar-subscripts] val[lex[i]] = i; ^ user.cpp:32:28: warning: array subscript has type ‘char’ [-Wchar-subscripts] nr += val[ch[j]] * p12; ^ user.cpp:12:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("zimeria.in", "r", stdin); ^ user.cpp:13:41: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("zimeria.out", "w", stdout); ^ user.cpp:16:30: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d %d", &var, &n); ^ user.cpp:17:17: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("\n"); ^ user.cpp:21:30: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%c", &lex[i]); ^ user.cpp:25:17: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("\n"); ^ user.cpp:28:22: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets (ch + 1); ^ /tmp/ccAo3NRP.o: In function `main': user.cpp:(.text.startup+0xc2): warning: the `gets' function is dangerous and should not be used.