Check out example codes for "how to change a string to an float in c++". It will help you in understanding the concepts better.

Code Example 1

#include <iostream>
#include <string>

int main() {
    std::string str = "123.4567";

    // convert string to float
    float num_float = std::stof(str);

    // convert string to double
    double num_double = std::stod(str);

   std:: cout<< "num_float = " << num_float << std::endl;
   std:: cout<< "num_double = " << num_double << std::endl;

    return 0;
}

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