Compilare: user.cpp: In function ‘int main()’: user.cpp:55:20: warning: array subscript has type ‘char’ [-Wchar-subscripts] if (t[ch]==0) ^ user.cpp:57:21: warning: array subscript has type ‘char’ [-Wchar-subscripts] t[ch]=++pr; ^ user.cpp:61:30: warning: array subscript has type ‘char’ [-Wchar-subscripts] else a[i][j]=t[ch]; ^ user.cpp:43:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("ferma3.in","r",stdin); ^ user.cpp:44:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("ferma3.out","w",stdout); ^ user.cpp:46:22: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &tip); ^ user.cpp:48:29: 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:54:28: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%c", &ch); ^ user.cpp:63:19: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("\n"); ^