The find_last_of() Family

The find_last_of() methods have these prototypes:

size_type find_last_of (const basic_string& str,
                        size_type pos = npos) const noexcept;
size_type find_last_of (const charT* s, size_type pos, size_type n) const;
size_type find_last_of (const charT* s, size_type pos = npos) const;
size_type find_last_of (charT c, size_type pos = npos) const noexcept;

These methods work like the corresponding rfind() methods, except that instead of looking for a match of the entire substring, they look for the last match for any single character in the substring.

Here’s code for finding the location of the last and next to last occurrences of any of the letters in "fluke" in a longer string:

string longer("That is a funny hat.");
string shorter("hat");
size_type loc1 = longer.find_last_of(shorter);  // sets loc1 to 18
size_type loc2 = longer.find_last_of("any");    // sets loc2 to 17

The last occurrence of any of the three letters of hat in longer is the t in hat. The last occurrence of any of the three characters of any in longer is the a in hat.