C++ float and double Different Precisions For Different Variables

#include <iostream>
#include <iomanip>

int main() {
    float a = 1.123456789f;
    double b = 1.123456789;

    std::cout << std::setprecision(10) << "Float: " << a << std::endl;
    std::cout << std::setprecision(20) << "Double: " << b << std::endl;

    return 0;

This code demonstrates the usage of float and double data types in C++. The float variable a is assigned the value 1.123456789f explicitly as a float, while the double variable b is assigned the value 1.123456789 implicitly as a double.

The program then uses std::setprecision() from the <iomanip> library to set the precision for output. It displays the value of the float variable a with a precision of 10 decimal places and the value of the double variable b with a precision of 20 decimal places using std::cout.

The output demonstrates the difference in precision between float and double types in C++, showcasing how a float can store up to approximately 7 decimal digits of precision while a double can store up to about 15-16 decimal digits of precision.