Collecting User Input

To collect an input from the user you can use scanf. It works with 2 parts. The first is the format of the input you are collecting, and the second is where the value(s) is being stored. In this case, %d is being used to collect an integer from the user.

printf("Enter a number > ");
int num;
scanf("%d", &num); // The program will wait here for a user input

printf("You entered %d\n", num);

OUTPUT:

Enter a number > 123
You entered 123

NOTE: In certain text editors, consider adding the following snippet at the beginning of your file to suppress warnings related to the scanf function: #define _CRT_SECURE_NO_WARNINGS

Collecting Floats

You can use %f  to collect a floating point number. (number with decimals)

printf("Enter a decimal number > ");
float myFloat;
scanf("%f", &myFloat);
printf("You entered %.4f\n", myFloat); // Set the display to 4 decimal places

OUTPUT:

Enter a decimal number > 3.14
You entered 3.14

For doubles you need to use %lf instead of %f

double myDouble;
scanf("%lf", &myDouble);

Collecting Chars

Use %c to capture 1 character from the user.

printf("Enter a character > ");
char myChar;
scanf("%c", &myChar);
printf("You entered %c\n", myChar);