Lonely Integer#

Overview#

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#

\(1 \leq N < 100\)

\(N \% 2 = 1\) (\(N\) is an odd number)

\(0 \leq A[i] \leq 100, \forall \epsilon [1,N]\)

Output Format#

Output , the number that occurs only once.

Sample Input:1#

1
1

Sample Output:1#

Sample Input:2#

3
1 1 2

Sample Output:2#

Sample Input:3#

5
0 0 1 2 1

Sample Output:3#

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.

Solution#

lonely-integer.sh#

#!/bin/bash
# shellcheck disable=SC2162,SC2034

# Read number of integers
read n

# Read array of integers
read -a int_array

# Init result for XOR
result=0
for i in "${int_array[@]}"; do
    result=$(("$result" ^ "$i"))
done

echo "$result"

Lonely Integer

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