Compilare: user.cpp: In function ‘int main()’: user.cpp:120:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("unicat.in", "r", stdin); ^ user.cpp:121:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("unicat.out", "w", stdout); ^ user.cpp:123:12: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(a); ^ user.cpp:124:12: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(b); ^ user.cpp: In function ‘void manacher(char*, int*)’: user.cpp:75:29: warning: ‘c’ may be used uninitialized in this function [-Wmaybe-uninitialized] int mir = c - (i-c); ^ /tmp/cc2LH2QZ.o: In function `main': user.cpp:(.text.startup+0x53): warning: the `gets' function is dangerous and should not be used.