How can I convert a string to an integer in C++ without relying on the stoi function for cryptocurrency-related operations?

3 answers

• Guldbrandsen RiberFeb 09, 2022 · 4 years ago
  One way to convert a string to an integer in C++ without using the stoi function is by using the stringstream class. You can create a stringstream object, pass the string to it, and then extract the integer value using the extraction operator >>. Here's an example: ```cpp #include <iostream> #include <sstream> int main() { std::string str = "12345"; std::stringstream ss(str); int num; ss >> num; std::cout << num << std::endl; return 0; } ``` This code will output 12345, which is the integer value of the string "12345".
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• Nikki KDec 12, 2020 · 5 years ago
  Another approach to convert a string to an integer in C++ is by using the atoi function from the cstdlib library. This function takes a const char* as input and returns the corresponding integer value. Here's an example: ```cpp #include <iostream> #include <cstdlib> int main() { std::string str = "98765"; const char* cstr = str.c_str(); int num = std::atoi(cstr); std::cout << num << std::endl; return 0; } ``` This code will output 98765, which is the integer value of the string "98765".
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• GeshboiMay 17, 2022 · 4 years ago
  If you're looking for a more efficient solution, you can use the std::from_chars function introduced in C++17. This function directly converts a string to an integer without any intermediate steps. Here's an example: ```cpp #include <iostream> int main() { std::string str = "54321"; int num; std::from_chars(str.data(), str.data() + str.size(), num); std::cout << num << std::endl; return 0; } ``` This code will output 54321, which is the integer value of the string "54321".
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