Use `std::reverse` from `
`std::string s = “hello”;`
`std::reverse(s.begin(), s.end());`
Use a loop with two pointers
`std::string s = “hello”;`
`int i = 0, j = s.size() – 1;`
`while (i < j) { std::swap(s[i], s[j]); ++i; --j; }`
Use a new string and append characters from back to front
`std::string s = “hello”;`
`std::string rev;`
`for (int i = s.size() – 1; i >= 0; –i) rev += s[i];`
Use reverse iterators
`std::string s = “hello”;`
`std::string rev(s.rbegin(), s.rend());`
Use recursion
`void reverseStr(std::string& s, int l, int r) { if (l >= r) return; std::swap(s[l], s[r]); reverseStr(s, l + 1, r – 1); }`