scanf() is the input version of the printf() function.
Here's the format:
#include <stdio.h> int scanf(const char *restrict format,...);
Here's a simple version of the format:
scanf("placeholder ",variable);
In this code, placeholder is a conversion character, and variable is a type of variable that matches the conversion character.
Unless it's a string (char array), the variable is prefixed by the & operator.
Here are some scanf() examples:
To read an integer value into the variable highscore.
scanf("%d",&highscore);
To read a floating-point value to be input, which is then stored in the temperature variable.
scanf("%f",&temperature);
To read character input and store it in the key variable.
scanf("%c",&key);
The %s placeholder is used to read in text, but only until the first white space character is encountered.
So a space or a tab or the Enter key terminates the string. firstname is a char array, so it doesn't need the & operator in the scanf() function.
scanf("%s",firstname);