#include<stdio.h>

float add(float,float);
float sub(float,float);
float product(float,float);
float divide(float,float);

void main()
{
float n1,n2;
char sym,choice;
printf("This Program is a program for calculator\n\n");
scanf("%f%c%f",&n1,&sym,&n2);
if(sym=='+')
printf("\n%f",add(n1,n2));
if(sym=='-')
printf("\n%f",sub(n1,n2));
if(sym=='*')
printf("\n%f",product(n1,n2));
if(sym=='/')
printf("%f",divide(n1,n2));
printf("\nDo you wish to continue[y/n]");
scanf("%s",&choice);
if(choice=='y'||choice=='Y')
main();
}

float add(float m1,float m2)
{
return(m1+m2);
}

float sub(float m1,float m2)
{
return(m1-m2);
}

float product(float m1,float m2)
{
return(m1*m2);
}

float divide(float m1,float m2)
{
return(m1/m2);
}

<?php
function canchi($nam)
{
$acan = array("Giap", "At", "Binh", "Dinh", "Mau", "Ky", "Canh", "Tan", "Nham", "Quy");
$achi = array("Ty", "Suu", "Dan", "Meo", "Thin", "Ty", "Ngo", "Mao", "Than", "Dau", "Tuat", "Hoi");
$can = $acan[($nam+6)%10];
$chi = $achi[($nam+8)%12];
return $can." ".$chi;
}
echo canchi(1988);
?>

Còn đây là C:

#include <stdio.h>
#include <conio.h>
void main()
{
unsigned nam;
char can[][5] = {"Giap", "At", "Binh", "Dinh", "Mau", "Ky",
"Canh", "Tan", "Nham", "Quy"};
char chi[][5] = {"Ty", "Suu", "Dan", "Meo", "Thin", "Ty",
"Ngo", "Mao", "Than", "Dau", "Tuat", "Hoi"};

printf("\nNhap nam can biet : ");
scanf("%d", &amp;amp;nam);
printf("Nam am lich cua %d la %s %s\n\n", nam, can[(nam+6)%10], chi[(nam+8)%12]);
getch();
}