Lonely_Integer-2.sh

# There are N integers in an array A. All but one integer occur in pairs. Your task is to find the number that occurs only once.

# Input Format

# The first line of the input contains an integer N, indicating the number of integers. The next line contains N space-separated integers that form the array A.

# Constraints
# 1<=N<100
# N%2==1 ( Nis an odd number)
# 0<=A[i]<=100, ∀i∈[1,N]
# Output Format

# Output ,S the number that occurs only once.

# Sample Input:1
# 1
# 1

# Sample Output:1

# 1
# Sample Input:2
# 3
# 1 1 2

# Sample Output:2
# 2

# Sample Input:3
# 5
# 0 0 1 2 1

# Sample Output:3

# 2
# Explanation

# In the first input, we see only one element (1) and that element is the answer.
# In the second input, we see three elements; 1 occurs at two places and 2 only once. Thus, the answer is 2.
# In the third input, we see five elements. 1 and 0 occur twice. The element that occurs only once is 2.


read
arr=($(cat)) 
echo "${arr[@]}" | tr ' ' '\n' |sort | uniq -u | tr '\n' ' '