Compilare: user.cpp: In function ‘int main()’: user.cpp:67:39: 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:68:41: 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:71:28: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%s%s", pat, txt); ^ user.cpp: In function ‘void KMPSearch(char*, char*)’: user.cpp:37:17: warning: ‘j’ may be used uninitialized in this function [-Wmaybe-uninitialized] if(pat[j] == txt[i]) { ^ user.cpp:37:27: warning: ‘i’ may be used uninitialized in this function [-Wmaybe-uninitialized] if(pat[j] == txt[i]) { ^