Format specifier string: Note: The major difference between printf and scanf is, In printf() we pass variable values whereas in scanf() we pass the variable address.
The only difference between sprintf() and printf() is that sprintf() writes data into a character array, while printf() writes data to stdout, the standard output device.
The scanf("%d",&number) statement reads integer number from the console and stores the given value in number variable. The printf("cube of number is:%d ",number*number*number) statement prints the cube of number on the console.
In C programming language, scanf is a function that stands for Scan Formatted String. It reads data from stdin (standard input stream i.e. usually keyboard) and then writes the result into the given arguments. It accepts character, string, and numeric data from the user using standard input.
Use of & in scanf() but not in printf()
As a and b above are two variable and each has their own address assigned but instead of a and b, we send the address of a and b respectively. The reason is, scanf() needs to modify values of a and b and but they are local to scanf().
The “%d” in scanf allows the function to recognise user input as being of an integer data type, which matches the data type of our variable number. The ampersand (&) allows us to pass the address of variable number which is the place in memory where we store the information that scanf read.
The printf() function sends a formatted string to the standard output (the display). This string can display formatted variables and special control characters, such as new lines ('\n'), backspaces ('\b') and tabspaces ('\t'); these are listed in Table 2.1.
In C language, scanf() function is used to read formatted input from stdin.
The scanf function reads input from the console and parses it. It has no means of printing anything.
The most basic printing functions would be puts and putchar which print a string and char respectively. f is for formatted. printf (unlike puts or putchar ) prints formatted output, hence printf. For example it can print an int in hexadecimal, or a float rounded to three decimal places, or a string left padded.
In C programming language, %d and %i are format specifiers as where %d specifies the type of variable as decimal and %i specifies the type as integer. In usage terms, there is no difference in printf() function output while printing a number using %d or %i but using scanf the difference occurs.
The real problem with scanf has a completely different nature, even though it is also about overflow. When scanf function is used for converting decimal representations of numbers into values of arithmetic types, it provides no protection from arithmetic overflow. If overflow happens, scanf produces undefined behavior.
The most basic printing functions would be puts and putchar which print a string and char respectively. f is for formatted. printf (unlike puts or putchar ) prints formatted output, hence printf. For example it can print an int in hexadecimal, or a float rounded to three decimal places, or a string left padded.
The main difference between them is: scanf() reads input until it encounters whitespace, newline or End Of File(EOF) whereas gets() reads input until it encounters newline or End Of File(EOF), gets() does not stop reading input when it encounters whitespace instead it takes whitespace as a string.
With scanf you are wanting to RETAIN some data, so you need a pointer aka address where the data you input will be stored even after you leave the function.
The real problem with scanf has a completely different nature, even though it is also about overflow. When scanf function is used for converting decimal representations of numbers into values of arithmetic types, it provides no protection from arithmetic overflow. If overflow happens, scanf produces undefined behavior.
An '\n' - or any whitespace character - in the format string consumes an entire (possibly empty) sequence of whitespace characters in the input.
Inputting Multiple Values
If you have multiple format specifiers within the string argument of scanf, you can input multiple values. All you need to do is to separate each format specifier with a DELIMITER - a string that separates variables.
%s tells printf that the corresponding argument is to be treated as a string (in C terms, a 0-terminated sequence of char ); the type of the corresponding argument must be char * . %d tells printf that the corresponding argument is to be treated as an integer value; the type of the corresponding argument must be int .
Definition. First of all, “gets” is a C library function that reads a line from stdin (standard input) and stores it in the pointed string. In contrast, “puts” is a C library function that writes a string to stdout or standard output. Thus, this is the basic difference between gets and puts in C Language.
In case of a string (character array), the variable itself points to the first element of the array in question. Thus, there is no need to use the '&' operator to pass the address.
In C programming language, %d and %i are format specifiers as where %d specifies the type of variable as decimal and %i specifies the type as integer. In usage terms, there is no difference in printf() function output while printing a number using %d or %i but using scanf the difference occurs.
'%f': Print a floating-point number in normal (fixed-point) notation. See Floating-Point Conversions, for details.
Save this answer. Show activity on this post. % indicates a format escape sequence used for formatting the variables passed to printf() . So you have to escape it to print the % character.