Missing Integer Problem

You are given a sequence of n-1 distinct positive integers, all of which are less than or equal to a integer ‘n’. You have to find the integer that is missing from the range [1,2,...,n]. Solve the question without using arrays.

Input Format:

One line containing the integer ‘n’ where 2<=n<=10,000

First line is followed by a sequence of ‘n-1’ distinct positive integers. Note that the sequence may not be in any particular order.

Output Format: 

One line containing the missing number.

#include<stdio.h>

int main()

{int n,i,b;

scanf("%d",&n);

int a[10000]={0};

for(i=1;i<=n;i++)

{

scanf("%d",&b);

a[b]=a[b]+1;}

for(i=1;i<=n;i++)

{

if(a[i]==0)

{

printf("%d",i);

}}return 0;

}