How to use scanf in c++

scanf() function is used to read formatted data from standard input. The usage is int scanf(const char* format, ...), where format specifies the format of the input data, and ... is the input variable. the address of. Format specifiers include %d (integer), %i (integer), %c (character), %f (floating point), %lf (double floating point). It should be noted that scanf() does not check the validity of the input data and only reads data from the standard input, which may cause the program to crash. The alternative is to use std::cin introduced in C 11 for input.

Usage of scanf() in C

scanf() function is used in C to read from standard input Standard library functions for devices to read formatted data. It can store various data types like int, char, float, etc. in a given variable.

Usage:

<code class="cpp">int scanf(const char* format, ...);</code>

Parameters:

• format: Specify the input data Format, consisting of format specifiers.
• ...：Enter the address of the variable.

Format specifier:

• %d: integer
• %i: Integer
• %c：Character
• %f：Floating point number
• %lf：Double precision floating point number

Example:

<code class="cpp">int x, y;
scanf("%d %d", &x, &y); // 从标准输入读取两个整数，并存储在 x 和 y 中</code>

Note:

• scanf( ) does not check whether the input data is valid, so invalid data entered by the user may cause the program to crash.
• scanf() only reads data from standard input and does not work with files or other input streams.
• If the input data does not conform to the specified format, scanf() will return an integer representing the number of successfully read variables. If there is an error in the input data, it will return EOF (-1).

Alternative method:

A new I/O library was introduced in C 11, providing safer and more flexible input and output operations. You can use std::cin for input:

<code class="cpp">int x, y;
std::cin >> x >> y;</code>

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