string find_last_not_of() in C++

find_last_not_of():Find last position of a character not in C string. It returns 

the index of last occurrence. 

Starting from __pos, searches backward for a character not 

contained in __s within this string. If found, returns the index where it was found. 

If not found, returns npos.

Parameters:

 __s – C string containing characters to avoid. 

__pos – Index of character to search back from (default end). 

Syntax:

str.find_last_not_of(__s, __pos)

For Example:

str = "bcabcdef"

str.find_last_not_of("a")=> It returns 7.

Approach

C++

#include <bits/stdc++.h>
using namespace std;

int main()
{
    string str = "bcabcdef";

    cout << str.find_last_not_of("a") << "\n";
    

    return 0;
}