Q:

# Write a C program to calculate age or Age Calculator

Write a C program to calculate age or Age Calculator.This program will read your date of birth and print the current age.

Age Calculator: This program will read your date of birth and print the current age. The logic is behind to implement this program – Program will compare given date with the current date and print how old are you?

It is a simple Program To Calculate Current Age of a Person by using Addition and Subtraction Operators. This C Program will calculate the age in Years, Months and Days.

Below is the source code of the C program to calculate age or Age Calculator which is successfully compiled and run on the windows system.The Output of the program is shown below.

## SOURCE : :

``````#include <stdio.h>
#include <time.h>

/*check given year is leap year or not*/
int isLeapYear(int year, int mon)
{
int flag = 0;
if (year % 100 == 0)
{
if (year % 400 == 0)
{
if (mon == 2)
{
flag = 1;
}
}
}
else if (year % 4 == 0)
{
if (mon == 2)
{
flag = 1;
}
}
return (flag);
}

int main()
{

int DaysInMon[] = {31, 28, 31, 30, 31, 30,
31, 31, 30, 31, 30, 31};
int days, month, year;
char dob[100];
time_t ts;
struct tm *ct;

/* enter date of birth */
printf("Enter your date of birth (DD/MM/YYYY): ");
scanf("%d/%d/%d",&days,&month, &year);

/*get current date.*/
ts = time(NULL);
ct = localtime(&ts);

printf("Current Date: %d/%d/%d\n",
ct->tm_mday, ct->tm_mon + 1, ct->tm_year + 1900);

days = DaysInMon[month - 1] - days + 1;

/* leap year checking*/
if (isLeapYear(year, month))
{
days = days + 1;
}

/* calculating age in no of days, years and months */
days = days + ct->tm_mday;
month = (12 - month) + (ct->tm_mon);
year = (ct->tm_year + 1900) - year - 1;

/* checking for leap year feb - 29 days */
if (isLeapYear((ct->tm_year + 1900), (ct->tm_mon + 1)))
{
if (days >= (DaysInMon[ct->tm_mon] + 1))
{
days = days - (DaysInMon[ct->tm_mon] + 1);
month = month + 1;
}
}
else if (days >= DaysInMon[ct->tm_mon])
{
days = days - (DaysInMon[ct->tm_mon]);
month = month + 1;
}

if (month >= 12)
{
year = year + 1;
month = month - 12;
}

/* print age */
printf("\n## Hey you are  %d years %d months and %d days old. ##\n", year, month, days);

return 0;
}``````

## OUTPUT : :

```Enter your date of birth (DD/MM/YYYY): 09/02/1997
Current Date: 17/3/2017

## Hey you are  20 years 1 months and 6 days old. ##```