Compilare: user.cpp: In function ‘void solve(char*, int&, int&)’: user.cpp:22:26: warning: converting to non-pointer type ‘char’ from NULL [-Wconversion-null] tok[m-1] = NULL; ^ user.cpp: In function ‘int main()’: user.cpp:42:14: warning: converting to non-pointer type ‘char’ from NULL [-Wconversion-null] *aux = NULL; ^ user.cpp:37:24: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin,"%d",&n); ^ user.cpp:39:28: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin,"%s",s1); ^