c++ explicit or code example

Example 1: explicit in c++ meaning

class String {
public:
    explicit String (int n); //allocate n bytes
    String(const char *p); // initialize sobject with string p
};

Example 2: explicit in c++ meaning

class String {
public:
    String(int n); // allocate n bytes to the String object
    String(const char *p); // initializes object with char *p
};