C code to find MISSING number in an array of integers from 1 to n with no duplicates,where a number will be missing.....

/*Author:Neelkant.S.Patil,GMIT,Davangere*/
#include<stdio.h>
#include<conio.h>
void main()
{
int i,j,n,a[100],b[100],miss;
clrscr();
printf("\nENTER THE SIZE OF THE ARRAY\n");
scanf("%d",&n);
printf("ENTER THE ELEMENTS IN THE ARRAY\n");
for(i=0;i<n;i++)
scanf("%d",&a[i]);
for(i=0;i<n;i++)
b[i]=i+1;
for(i=0;i<n;i++)
{
miss=0;
for(j=0;j<n;j++)
{
if(b[i]!=a[j])
{
//printf("MISSING IS %d\n",b[j]);
miss++;
}
if(miss==n)
printf("MISSING is %d\n",b[i]);


}
}
getch();
}
OUTPUT:
ENTER THE SIZE OF THE ARRAY
5
ENTER THE ELEMENTS IN THE ARRAY
1
2
4
5
6
MISSING is 3