Compilare: user.cpp: In function ‘int main()’: user.cpp:38:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<length_of_word; i++) x+=power[i]*(word[i]-'a'); ^ user.cpp:42:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<length_of_word; i++) x+=power[i]*(text[i]-'a'); ^ user.cpp:45:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=length_of_word; i<length_of_text; i++) ^ user.cpp:23:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("abc2.in", "r", stdin); ^ user.cpp:24:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("abc2.out", "w", stdout); ^ user.cpp:26:15: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(text); ^ user.cpp:45:15: warning: ‘length_of_word’ may be used uninitialized in this function [-Wmaybe-uninitialized] for(int i=length_of_word; i<length_of_text; i++) ^ /tmp/cc7EPnHe.o: In function `main': user.cpp:(.text.startup+0x56): warning: the `gets' function is dangerous and should not be used.