A library is a collection of subprograms used to develop other programs and software.
The C++ standard library contains files containing the standard functions that our program may use. These files are known as header files.
This is a standard input output package which stores the functions which are needed to perform input output operation.
The functions of stdio.h are ferror, fscanf, fwrite, putw etc.
Math function is used to declare the prototypes for the mathematical function and math error handlers. The routine in math.h performs mathematical calculation and conversion.
The math functions available in C++ are acos, atan, fabs, sqrt, div, exp etc.
The syntax of isdigit() is
int isdigit(int ch); // where isdigit checks whether the given character is a digit or not.
The string functions available in C++ are strcat(), strlen(), strcpy(), strcmp() etc.
In C++ all devices are treated as files. Thus the standard input devices, standard output devices and the standard error device are all treated as files. At its lowest level, a file is interpreted simply as a sequence, or a stream of bytes. At this level the notation of a data type is absent i.e., data is treated simply as sequence of bytes without considering its data type. However, at the user level, a file consists of a sequence of possibly intermixed data types-characters, arithmetic characters and class objects.
char s, s1;
cout<<"\n enter the first string \n;
int len= strlen(s1);
This function is used to convert its argument to lowercase letter if its argument is a letter.
int num, rndum;
cin >> num;
rndum = random(num) + 7;
for ( int n=1;n<=rndum; n++)
cout << n<< " " ;
Pow() function is used to find the power of the given number.
Exp() function is used to find the value of e raise to the power value.
The syntax for strcmp() function is
Int strcmp(const char *str1, const char *str2);)
The functions used to perform random data are rand(), srand(), random() and randomize().