What is the reason for using the explicit keyword in programming?

The explicit keyword in C++ is used to prevent implicit type conversions when calling constructors with a single parameter. If a constructor is marked as explicit, the compiler will not automatically use it for type conversions, which helps avoid unexpected errors.

For example:

class MyClass {
public:
    explicit MyClass(int x) { /*...*/ }
};

MyClass obj = 10; // Compilation error because the constructor is explicit
MyClass obj2(10); // Correct

Thus, explicit increases code safety by making conversions explicit.