int sym_delete_cols(sym_environment *env, int num, int * indices)
This routine is used to delete columns from the original problem description.
| sym_environment *env | INOUT | Pointer to the SYMPHONY environment. | 
| int num | IN | An integer indicating the number of columns to be deleted. | 
| int *indices | IN | Pointer to an integer type array indicating the indices of the columns to be deleted and having a size of at least num. | 
| FUNCTION_TERMINATED_NORMALLY | Function invoked successfully. | 
| FUNCTION_TERMINATED_ABNORMALLY | Function invoked unsuccessfully or one of the indices | 
| is out of the range of [0, number of variables-1] |