Compilare: user.cpp: In function ‘int main()’: user.cpp:21:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i=0;i<=strlen(s2)-strlen(s1);i++) ^ user.cpp:14:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("strmatch.in","r",stdin); ^ user.cpp:15:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("strmatch.out","w",stdout); ^ user.cpp:16:16: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(buffer); ^ user.cpp:18:16: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(buffer); ^ /tmp/ccgZS6j3.o: In function `main': user.cpp:(.text.startup+0x5a): warning: the `gets' function is dangerous and should not be used.