Compilare: user.cpp: In function ‘int sim()’: user.cpp:24:36: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if( X[ st[1] ].size() <= i+cnt ) continue; ^ user.cpp:26:40: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if( X[ st[j] ].size() <= i+cnt || X[ st[j]][i+cnt] != X[ st[1] ][i+cnt] ) ^ user.cpp: In function ‘int main()’: user.cpp:47:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("ratina.in","r",stdin); ^ user.cpp:48:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("ratina.out","w",stdout); ^ user.cpp:50:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d\n", &n, &m); ^ user.cpp:53:34: warning: ignoring return value of ‘char* fgets(char*, int, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fgets( c , 5005 , stdin ); ^ user.cpp:58:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d",&n); ^ user.cpp:60:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d ",&st[j]); ^