#include <algorithm>

For shift_left(For first, For last, difference_type n);           // C++20
For shift_left(Exec pol, For first, For last, difference_type n);

Verschiebt die Elemente des Bereichs [first, last) um n Positionen nach links.

Rückgabewert: first+(last-first-n) für n < last-first, sonst first.

shift_right().

shift_left.cpp

#include <algorithm>
#include <iostream>
#include <string>
 
int main()
{
  std::string s = "Hallo, Welt";
 
  std::shift_left(begin(s), end(s), 5);
 
  std::cout << s << '\n';
}