Compilare: user.cpp: In function ‘int common_prefix(int, int)’: user.cpp:15:96: warning: NULL used in arithmetic [-Wpointer-arith] while(words[pointer][result]==words[dictionary[position]][result]&&words[pointer][result]!=NULL) ^ user.cpp: In function ‘int binary_string_search(int)’: user.cpp:26:38: warning: NULL used in arithmetic [-Wpointer-arith] if(words[pointer][position]==NULL&&words[dictionary[middle]][position]==NULL) ^ user.cpp:26:81: warning: NULL used in arithmetic [-Wpointer-arith] if(words[pointer][position]==NULL&&words[dictionary[middle]][position]==NULL) ^ user.cpp: In function ‘int get_maximum_prefix(int)’: user.cpp:55:62: warning: unused variable ‘auxiliar’ [-Wunused-variable] int position=binary_string_search(pointer),position_copy,auxiliar,maximum_prefix=0; ^ user.cpp: In function ‘int main()’: user.cpp:78:54: warning: format ‘%d’ expects argument of type ‘int*’, but argument 3 has type ‘char*’ [-Wformat=] while(fscanf(fin,"%d %s",&operations[n],&words[n])==2){ ^ user.cpp:78:54: warning: format ‘%s’ expects argument of type ‘char*’, but argument 4 has type ‘char (*)[21]’ [-Wformat=] user.cpp: In function ‘int binary_string_search(int)’: user.cpp:20:56: warning: ‘maximum_position’ may be used uninitialized in this function [-Wmaybe-uninitialized] int left=1,right=dictionary_size+1,middle,position,maximum_position,maximum_common=0; ^