The role of scanf in c++

The role of scanf in C

scanf is a standard library function in C used to read data from the standard input device (usually the keyboard). It allows the user to specify a format string that instructs the program on how to interpret and store input.

Syntax

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

Among them:

• format: A format string specifying the data to be read type and format.
• ...: A series of variable parameters, representing pointers to store input data.

Uses

scanf is used to read formatted data from users or files. It can read a variety of data types, including integers, floating point numbers, characters, and strings.

Format specifiers

Format strings use format specifiers to specify the type and format of data to be read. Common format specifiers include:

• %d: signed decimal integer
• %u: unsigned decimal integer
• %f: single precision floating point number
• %lf: double precision floating point number
• %c: single character
• %s: string (until encountering a space)

Usage example

<code class="cpp">int main() {
    int age;
    float height;
    char name[50];

    printf("Enter your age: ");
    scanf("%d", &age);

    printf("Enter your height (in meters): ");
    scanf("%f", &height);

    printf("Enter your name: ");
    scanf("%s", name);

    return 0;
}</code>

Note Note

• #The scanf function may cause a buffer overflow and should be used with extreme caution.
• The scanf function does not verify whether the input is legal, so the user may enter invalid data.
• The scanf function cannot read spaces, so if you want to read space-delimited input, you need to use other methods.

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