Fibonaci Closest Number v2

//   Functions
//   Simeon Baltadziev
//   09.05.2017
//   C programming basics

#include <stdio.h>


int fibonacciNumber(int enteredNumber) {
    int i;
    //int enteredNumber;
    printf("Enter fibonacci's number: ");
    scanf("%d", &enteredNumber);
    // Checks if input value is 0 or negative number
    if(enteredNumber == 0) { printf("Error: Input larger number than 0"); }
    if(enteredNumber <0)   { printf("Error: Input possitive number"); }
    int a = 1, b =1; // Declaring the fisrt two fibonacci numbers
    for(i = 0; i<=enteredNumber;i++) {
        // Fibonacci Number Formula
        b = a-b;
        a = a+b;
        }
    if(enteredNumber>0) {    return b; }

}

 long long fibonacciNumberDifference(long long enteredNumber){

 int j = 0;
 int i = 0;
 long  arrayNumber[40];
 long  difference = 10;
 long  minDifference = 100000;
 long  number = 0;

     long long a = 1, b =1; // Declaring the fisrt two fibonacci numbers
      for(i = 0; i<=40;i++) {
        // Fibonacci Number Formula
        b = a-b;
        a = a+b;
        arrayNumber[i] = b;
        //prlong long f("%d\n", b);

        }

  for(j = 0; j<=40; j++) {
    long long  diff = 0;
              long   diff2 = 0;
              if(enteredNumber > arrayNumber[j] && enteredNumber < arrayNumber[j+1]) {
       //prlong long f("number 1 and two %d,%d\n", arrayNumber[j], arrayNumber[j+1]);

              diff =  enteredNumber - arrayNumber[j];
              diff2 = enteredNumber - arrayNumber[j+1];
              if (diff < 0) { diff = diff*(-1); }
              if (diff2< 0) { diff2 = diff2*(-1);}
              if (diff<diff2) { minDifference = diff; number = j;}
              if (diff2<diff) { minDifference = diff2; number = j+1;}
              //prlong long f("diff1 and 2 %d, %d\n", diff,diff2);
              printf("The closest number is: %ld\n", arrayNumber[number]);
              printf("The difference is: %ld\n", number);
              return arrayNumber[number];

              }

        }
}


main()
{
 long enteredNumber; scanf("%ld", &enteredNumber);
 long number = fibonacciNumber(enteredNumber);
 fibonacciNumberDifference(enteredNumber);


 //printf("Diffrence: %ld\n", numberInArray);
 return 0;

}