Create string with specified number of characters

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Taking a look at the constructor reference of basic_string, one can see that there is no easy way of repeating a complete string. For a single character, you could use (2) like this:

std::string s(5, 'a'); // s == "aaaaa"

For generating a string repetition, you’ll need some workaround. It’s easier to do this post-construction by simply filling the string with, for example, std::generate (having fun with algorithms).

#include <string>
#include <algorithm>

// ...

std::string pattern("Xeo ");
auto pattern_it = pattern.begin();
std::string s(256, '\0');
std::generate(s.begin(), s.end(),
    [&]() -> char { 
      if(pattern_it == pattern.end())
        pattern_it = pattern.begin();
      return *pattern_it++; // return current value and increment
    });

Live example.

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