C User Input

scanf reads input typed by the user. You pass the address of the variable with &. This example reads from the keyboard, so on your own computer it waits for you to type; here it is shown with the input 7.

ExampleC

#include <stdio.h>

int main(void) {
  int number;
  printf("Type a number: ");
  scanf("%d", &number);
  printf("Your number plus one is %d\n", number + 1);
  return 0;
}

Output

Type a number: Your number plus one is 8

Quick check

Why does scanf need &number instead of number?

It needs the memory address to store the valueTo make it fasterIt does not; & is optional

Finish the quick check (and any code exercise) to complete this lesson, or mark it done yourself.

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