This program is designed to print a Fortune Cookie message for a positive integer entered by the user. Code: int sum_digits(int); void print_cookie(int); int main(void) { int number, // input sum; // the sum of the digits for the number printf("Enter a positive integer: "); scanf("%d", &number); sum= sum_digits(number); print_cookie(sum); return 0; } int sum_digits(int number) { int remainder, sum_int; while(number!=0 && remainder!=0) { sum_int= sum_int+ number- number/10*10; number= number/10; remainder=sum_int%10; if(number==0 && remainder!=0) { number=sum_int; sum_int=0; } } return sum_int; } void print_cookie(int sum) { switch(sum) { case 1: printf("You will have a fine capacity for the enjoyment of life.\n"); break; case 2: printf("Now is the time to try something new.\n"); break; case 3: printf("Don't let doubt and suspicion bar your progress.\n"); break; case 4: printf("Your principles mean more to you than any money or success.\n"); break; case 5: printf("Accept the next proposition you hear.\n"); break; case 6: printf("A handful of patience is worth more than a bushel of brains.\n"); break; case 7: printf("You have an active mind and a keen imagination.\n"); break; case 8: printf("You are talented in many ways.\n"); break; case 9: printf("Treat everyone as a friend.\n"); break; } } The function of the function sum_digits is to calculate the sum of the digits of the input number and the sum must be a single digit since the fortune numbers are single digited so if the sum exceeds one digit, add them together e.g. input number is 12345 sum= 1+2+3+4+5 sum= 15 sum= 1+5 sum= 6