compare to pervious values

How can I compare a previous value with a current value to analysis the input of each day with a while loop?
The input's times are defined by the user; as "printf("Enter the number in day %d: ", days); scanf("%d", &number)

I want to set a current day = previous day outside the while loop, but how to compare in the loop again each time?

This program is ok, except the twice value.

Code:

---

/*  Purpose of this program: Analytics of clicking on a web-based
*/


  #include <stdio.h>
   


    int main() {
 
    int days; /* with days++ in looping to count the input days */
    int daysPeriod; /* Input the days are needed to analytics */
    int highest; /* Highest value  */
    int lowest; /*Lowest value */
    int more500; /* Click more than 500 */
    int click; /* number of click each loop */
    int sumClick; /* Total click value */
    int twice; /* count the clicks that more than twice for previouse day */
    int currentday, hold;
   
    /*initialize vlaue*/
    click =0;
    highest=0;
    lowest=2.e2; /* let the lowest to be max value for easy to compare the input value. */
    twice = 0;
    hold = 0;
    currentday = 0;
    sumClick = 0;
    days = 1;
   
    /* Read how many days are need to analytis */
    printf("Enter the period of click analytics (number of days): ");
    scanf("%d", &daysPeriod);
   
    /* Using a while loop to count the input day for analytics, the input day at lease is 1 day. */
    while (days <= daysPeriod) {


    /* Read how many clicks per day within while loop for daysPeriod, as input's day. */
    printf("Enter the clicks in day %d: ", days);
    scanf("%d", &click);
    fflush(stdin);


    hold = click; /*unused*/
   
    /* Checking the value of click is value highest or lowest */
    if (click > highest)
    {
    highest = click;}


 if (click < lowest){
  lowest = click;}
 
    /* Checking the value of click, if over 500 times, the value of more500 will be counted. */
  if(click >= 500)
  {
  more500++;
  }
 
  /* Checking the value of currentday, if the click of pervious day is more then current day 2 times,
    the value of twice will be counted */
  if(currentday/2 < click)
  {
  currentday = click;
  twice++;
    }
   
   
  /* Add the total click's value each loop, then put it into sum of click, as sumClick */
    sumClick += click;
   
    /* This days will be added each loop until all input's days are counted; as days will be equal to dayPeriod. */
    days++;
    }

    /* printout the click's results of average, highest, lowest, click more than 500 and clicks twice more than the previous day. */

    printf("Average click is: $%d\n", sumClick / daysPeriod);
    printf("Highest clicks is %d\n", highest);
    printf("Lowest clicks is %d\n", lowest);
    printf("Number of days with clicks more than 500 is %d\n", more500);
    printf("Number of days with clicks twice of previous day: %d\n", twice);


    return 0;
    }

---

A better indentation style would help.
Indentation style - Wikipedia

Like so

Code:

---

/*  Purpose of this program: Analytics of clicking on a web-based
*/
#include <stdio.h>

int main()
{
  int days;                    /* with days++ in looping to count the input days */
  int daysPeriod;              /* Input the days are needed to analytics */
  int highest;                  /* Highest value  */
  int lowest;                  /*Lowest value */
  int more500;                  /* Click more than 500 */
  int click;                    /* number of click each loop */
  int sumClick;                /* Total click value */
  int twice;                    /* count the clicks that more than twice for previouse day */
  int currentday, hold;

  /*initialize vlaue */
  click = 0;
  highest = 0;
  lowest = 2.e2;                /* let the lowest to be max value for easy to compare the input value. */
  twice = 0;
  hold = 0;
  currentday = 0;
  sumClick = 0;
  days = 1;

  /* Read how many days are need to analytis */
  printf("Enter the period of click analytics (number of days): ");
  scanf("%d", &daysPeriod);

  /* Using a while loop to count the input day for analytics, the input day at lease is 1 day. */
  while (days <= daysPeriod) {
    /* Read how many clicks per day within while loop for daysPeriod, as input's day. */
    printf("Enter the clicks in day %d: ", days);
    scanf("%d", &click);
    fflush(stdin);  //!! BAD

    hold = click;              /*unused */

    /* Checking the value of click is value highest or lowest */
    if (click > highest) {
      highest = click;
    }
    if (click < lowest) {
      lowest = click;
    }

    /* Checking the value of click, if over 500 times, the value of more500 will be counted. */
    if (click >= 500) {
      more500++;
    }

    /* Checking the value of currentday, if the click of pervious day is more then current day 2 times,
      the value of twice will be counted */
    if (currentday / 2 < click) {
      currentday = click;
      twice++;
    }

    /* Add the total click's value each loop, then put it into sum of click, as sumClick */
    sumClick += click;

    /* This days will be added each loop until all input's days are counted; as days will be equal to dayPeriod. */
    days++;
  }

  /* printout the click's results of average, highest, lowest, click more than 500 and clicks twice more than the previous day. */
  printf("Average click is: $%d\n", sumClick / daysPeriod);
  printf("Highest clicks is %d\n", highest);
  printf("Lowest clicks is %d\n", lowest);
  printf("Number of days with clicks more than 500 is %d\n", more500);
  printf("Number of days with clicks twice of previous day: %d\n", twice);

  return 0;
}

---

Code:

---

    /* Checking the value of currentday, if the click of pervious day is more then current day 2 times,
      the value of twice will be counted */
    if (currentday / 2 < click) {
      currentday = click;
      twice++;
    }

---

Better variable names would help.

Code:

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    if (yesterdayClicks / 2 < todaysClicks) {
      yesterdayClicks = todaysClicks;
      twice++;
    }

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