#include<stdio.h>
void main()
{
        int a,b,c;
        printf("1<=a,b,c<=100\n\n");
        printf("a,b and c are integer\n\n");
        printf("\nEnter 1st pole heights:- ");
        scanf("%d",&a);
        printf("\nEnter 2nd pole heights:- ");
        scanf("%d",&b);
        printf("\nEnter 3rd pole heights:- ");
        scanf("%d",&c);
        if(b-a==c-b)
                printf("This arrangement of pole is beautiful");
        else
                printf("This arrangement of poles is not beautiful");
}
