Compilare: user.cpp: In function ‘int main()’: user.cpp:18:29: warning: array subscript has type ‘char’ [-Wchar-subscripts] if(v[j]=='#')a[i][j]=-1; ^ user.cpp:21:20: warning: array subscript has type ‘char’ [-Wchar-subscripts] b[i][j]=v[j]-'A'+1; ^ user.cpp:10:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("miting.in","r",stdin); ^ user.cpp:11:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("miting.out","w",stdout); ^ user.cpp:12:33: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d\n",&cer,&n,&m); ^ user.cpp:13:14: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(cuv); ^ user.cpp:16:18: warning: ignoring return value of ‘char* gets(char*)’, declared with attribute warn_unused_result [-Wunused-result] gets(v+1); ^ /tmp/ccIkGt1K.o: In function `main': user.cpp:(.text.startup+0x86): warning: the `gets' function is dangerous and should not be used.