Compilare: user.cpp: In function ‘int String_to_int(char*)’: user.cpp:18:17: warning: array subscript has type ‘char’ [-Wchar-subscripts] if(vc[s[i]]==0) ^ user.cpp:19:17: warning: array subscript has type ‘char’ [-Wchar-subscripts] vc[s[i]]=val++; ^ user.cpp:20:19: warning: array subscript has type ‘char’ [-Wchar-subscripts] s[i]=vc[s[i]]; ^ user.cpp: In function ‘int main()’: user.cpp:71:25: warning: converting to non-pointer type ‘char’ from NULL [-Wconversion-null] char cuv[27]={NULL}; ^ user.cpp:79:25: warning: converting to non-pointer type ‘char’ from NULL [-Wconversion-null] char cuv[27]={NULL}; ^ user.cpp:68:21: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(in,"%d ",&n); ^ user.cpp:72:27: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(in,"%s ",cuv); ^ user.cpp:75:21: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(in,"%d ",&n); ^ user.cpp:80:27: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(in,"%s ",cuv); ^