A AB ABC ABCD ABCDE
#include<stdio.h>
#include<conio.h>
void main()
{
char i,j,n;
clrscr();
printf("enter the value of n :");
scanf("%d",&n);
//value of n is not greater then 90
for(i=65;i<=n;i++)
{
for(j=65;j<=i;j++)
{
printf("%c",j);
}
printf("\n");
}
getch();
}