I couldn't figüre out how to add values to the date. Imagine, I have a date like 2012-5-15. After I parsed it, I obtained the year,month and day seperately and I tried to convert to my exact date to the days by using time\_t and mktime. Do I have a chance to convert it back to the date from the days or seconds I found? Here is part of my code trying to do this;

```
if(operation="+"){
    tm tm1=make_tm(year,mon,day);
    time_t time1=mktime(&tm1);
    int seconds_per_day=60*60*24;
    time_t second=time1/seconds_per_day;
    int sum=second //Trying to convert to the int from my time_t, don't know      
                   //if it is neccesary
    sum=sum+value //the value I want to add 

```

So, basically if I give an input like 2012/5/15. It calculates how many days it passed by using the method but I just need to convert it to date and make it shown. Do you have any idea?