/* Perfect Square - Program to find four digit perfect squares, where the number represented by the first two digits and the number represented by the last two digits are also perfect squares. */

/* For eg 1681=41^2  16=4^2  81=9^2 */

#include  <stdio.h>
#include  <conio.h>
#include  <math.h>

void main()
{
    int  n, n1, n2, i, flag1, flag2, flag3 ;
    clrscr() ;
    printf("Four digit perfect squares with required property are as shown:\n");
    for(n=1000 ; n<=9999 ; n++)
        {
            n1=n%100 ;  /*Extracting last two digits*/
            n2=n/100 ;   /*Extracting first two digits*/
            /*Checking whether the first two digits are perfect squares*/
            flag1=0 ;
            i=sqrt(n2) ;  /* Remember i is integer whereas sqrt() returns double */
            if(n2==i*i)
                flag1=1 ;
            /*Checking whether the last two digits are perfect squares*/
            flag2=0 ;
            i=sqrt(n1) ;
            if(n1==i*i)
                flag2=1 ;
            /*Checking whether the number itself is a perfect square*/
            flag3=0 ;
            i=sqrt(n) ;
            if(n==i*i)
                flag3=1 ;
            if(flag1==1 && flag2 ==1 && flag3==1)
                printf("%d ", n) ;
        }
    getch() ;
}

/*
Output

Four digit perfect squares with required property are as shown:
1600 1681 2500 3600 4900 6400 8100
*/