Submitted by careerstack
This is a function that compares two strings lexicographically without considering the case of the string so 'Bat' and 'bat' are equivalent in the comparison.
It returns -1 if a < b, 1 if a > b and 0 if a == b
a string link 'ba' will be < 'Bat'
tolower is a function defined in ctype.h
int compare_fn (string a,string b)
{
string:: iterator it1;
string:: iterator it2;
for(it1=a.begin(),it2=b.begin();it1!=a.end()&&it2;!=b.end();it1 ,it2 )
{
if(tolower(*it1) < tolower(*it2))
return -1;
else if(tolower(*it1) > tolower(*it2))
return 1;
}
if(it1==a.end() && it2!=b.end())
return -1;
if(it1!=a.end() && it2==b.end())
return 1;
else
return 0;
}
