The input contains nine different numbers, which are 1 to 9 in some random order, for example, 4 1 5 9 8 7 3 6 2. Now, start from the first place, we get the number 4. It indicates that the next number we need to pick is at the 4th place, which is 9. Likewise, we then go the 9th place and get the number 2. We repeat this process until we go to a place that has already been visited. In this example, we will stop at the second place and get the number 1, because we have found a circle. Therefore, along the way we pick four numbers, 4 9 2 1, and the output is the sum of these numbers, which is 16.
Note that we always start from the first place.
Other examples: Consider the input 2 3 4 5 6 7 8 9 1, the output should be 45 since we will visit the numbers one by one and go back to the beginning. Consider the input 1 9 8 7 6 5 4 3 2, the output should be 1 since we stop immediately and cannot go anywhere. Consider the input 9 2 3 4 5 6 7 8 1, the output should be 10.
A random sequence of the nine different numbers of 1 to 9.
The sum of the numbers being visited. Remember to print a '\n' at the end of the sum.