program in c++ to compare two strings and return 0 if the two strings are equal and -1 is strings are unequal

Answer 1

just do

#include <string>
short compare(const std::string &a, const std::string &b)
{
return (a == b) ? 0 : -1;
}

or

#include <string>
bool compare(const std::string &a, const std::string &b)
{
return (a == b);
}

or just

a == b

Answer 2

Hint:
Use compare() method from the string class.