#include <stdio.h>

int main(void)
{
  int  number, digits;
  
  digits = 0;  /* This variable counts the digits. Initially it is 0. */

  printf("This program counts the number of digits in an integer.\n");
  
  printf("Enter a nonnegative integer:  ");
  
  scanf("%d", &number);

  /* We  have to execute the body of this loop at least once anyway,  and
     for this reason, do-while is more convenient here than a while-loop. */

  do { /* start loop body */
  	number = number /10;   /* note we do integer division here */
  	digits++;              /* each time we increase the counter */
  	} /* end loop body */
  	while ( number > 0 ) ;  /* evaluate termination condition */ 

  /* Notice we have to write ";" after the while(condition) to show
     this is the end of do-while loop statement */

  printf("The number has %d digits.\n", digits);
  
  return 0;
}