Excel element no to sheet address program in c

#include<stdio.h>
main()
{
 int n,a[20],r,i=0,j;
 clrscr();
 printf("enter element:\n");
 scanf("%d",&n);
 while(n>0)
 {
  r=n%26;
  if(r==0)
  {
   r=26;
   n=n-1;
  }
  a[i]=r;
  i++;
  n=n/26;
 }
 for(j=i-1;j>=0;j--)
  printf("%c",a[j]+64);
 getch();
} 

Arrange Array Elements Using Array Index

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

 /* arrange array */
 main()
 {
  int i[5]={4,3,1,0,2};
  int val[5]={7,9,10,1,8};
  int j,pos,tmp,tmp_pos;
  int x,y;

  for(x=0;x<=3;x++)
  {
  for(y=x+1;y<=4;y++)
  {
   if(i[x]>i[y])
   {
    tmp=val[x];
    val[x]=val[y];
    val[y]=tmp;
    tmp=i[x];
    i[x]=i[y];
    i[y]=tmp;
   }
  }
  }

  clrscr();


  for(j=0;j<=4;j++)
  printf("%3d,",val[j]);


}