#include <iostream>
#include <string>
#include <algorithm>
#include <assert.h>
 
void RemoveCharacterFromString(char character_for_remove, std::string &string) {
  auto it = std::remove_if(std::begin(string), std::end(string),
                           [=](char c) { return c == character_for_remove; });
  string.erase(it, std::end(string));
}
 
void RemoveAllCharactersInRangeFromString(char from, char to,
                                          std::string &string) {
  assert(from <= to);
  for (auto curr_character = from; curr_character <= to; ++curr_character) {
    RemoveCharacterFromString(curr_character, string);
  }
}
 
int main() {
  std::string string = "aaa bbb ccc ddd ccc fff eee ggg fff";
  RemoveAllCharactersInRangeFromString('c', 'f', string);
  std::cout << "after remove: " << string << '\n';
}

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