[prev] 48 [next]

Application: Input Using scanf()

Standard I/O function scanf() requires the address of a variable as argument
  • scanf() uses a format string like printf()
  • use %d to read an integer value 

    #include <stdio.h>
…
int answer;
printf("Enter your answer: ");
scanf("%d", &answer);

  • use %f to read a floating point value   (%lf for double) 

    float e;
printf("Enter e: ");
scanf("%f", &e);

  • scanf() returns a value — the number of items read
    • use this value to determine if scanf() successfully read a number
      • scanf() could fail e.g. if the user enters letters