Answers for "find a character in string c++"

find character in string c++

auto char_to_find = 'a'
if (str.find(char_to_find) != std::string::npos) {
    // character found
}

index string c++

#include <string>
#include <iostream>

int main(){
  //index string by using brackets []
  std::string string = "Hello, World!";
  //assign variable to string index
  char stringindex = string[2];
  
}

std string find character c++

// string::find
#include <iostream>       // std::cout
#include <string>         // std::string

int main ()
{
  std::string str ("There are two needles in this haystack with needles.");
  std::string str2 ("needle");

  // different member versions of find in the same order as above:
  std::size_t found = str.find(str2);
  if (found!=std::string::npos)
    std::cout << "first 'needle' found at: " << found << 'n';

  found=str.find("needles are small",found+1,6);
  if (found!=std::string::npos)
    std::cout << "second 'needle' found at: " << found << 'n';

  found=str.find("haystack");
  if (found!=std::string::npos)
    std::cout << "'haystack' also found at: " << found << 'n';

  found=str.find('.');
  if (found!=std::string::npos)
    std::cout << "Period found at: " << found << 'n';

  // let's replace the first needle:
  str.replace(str.find(str2),str2.length(),"preposition");
  std::cout << str << 'n';

  return 0;
}

c++ find string in string

#include <iostream>
#include <string>
#include <algorithm>
#include <functional>

int main()
{
    std::string in = "Lorem ipsum dolor sit amet, consectetur adipiscing elit,"
                     " sed do eiusmod tempor incididunt ut labore et dolore magna aliqua";
    std::string needle = "pisci";
    auto it = std::search(in.begin(), in.end(),
                   std::boyer_moore_searcher(
                       needle.begin(), needle.end()));
    if(it != in.end())
        std::cout << "The string " << needle << " found at offset "
                  << it - in.begin() << 'n';
    else
        std::cout << "The string " << needle << " not foundn";
}